Remove more references to epoch and add warning

Author: lhstrh

docs/developer/downloading-and-building.mdx

@@ -51,9 +51,5 @@ However, we would suggest to choose an IDE that comes with good Java (and
 ideally Kotlin) support and that integrates well with Gradle.
 We recommend to use our [IntelliJ setup](../developer/developer-intellij-setup.mdx).
 
-## Building IDEs
-
-Currently, we provide two IDEs that support Lingua Franca programs.
-Their source code is located in external repositories.
-We have a [Lingua Franca extension](https://github.com/lf-lang/vscode-lingua-franca) for VS code and an Eclipse based IDE called [Epoch](https://github.com/lf-lang/epoch).
-Please refer to the READMEs for build instructions.
+## Building the VS Code extension
+To build the [Lingua Franca extension](https://github.com/lf-lang/vscode-lingua-franca) for VS Code, refer to the README in the source repository.

docs/legacy_routing.ts

@@ -11,10 +11,6 @@ export default [
     "to": "/deprecated",
     "from": "/docs/handbook/language-specification"
   },
-  {
-    "to": "/docs/tools/epoch-ide",
-    "from": "/docs/handbook/epoch-ide"
-  },
   {
     "to": "/docs/tools/code-extension",
     "from": "/docs/handbook/code-extension"

docs/sidebars.ts

@@ -120,10 +120,6 @@ const sidebars: SidebarsConfig = {
           "type": "doc",
           "id": "tools/code-extension"
         },
-        {
-          "type": "doc",
-          "id": "tools/epoch-ide"
-        },
         {
           "type": "doc",
           "id": "tools/command-line-tools"

docs/tools/epoch-ide.mdx

@@ -20,14 +20,12 @@ $ lfc src/MyFile.lf
 ... successful compile ...
 ```
 
-If you then have trouble compiling the same file using [Epoch](../tools/epoch-ide.mdx) or the [Visual Studio Code extension](../tools/code-extension.mdx), then those tools are executing in a different environment that may not have the same `PATH` variable and may, for example, fail to find some external program or invoke a different version of that program.
+If you then have trouble compiling the same file using the [Visual Studio Code extension](../tools/code-extension.mdx), then it is executing in a different environment that may not have the same `PATH` variable and may, for example, fail to find some external program or invoke a different version of that program.
 
-On many platforms, one way to ensure that [Epoch](../tools/epoch-ide.mdx) and the [Visual Studio Code extension](../tools/code-extension.mdx) use the same environment as the command-line tools is to invoke them on the command line. For example, on a Mac, you can invoke Epoch and Visual Studio Code as follows:
+On many platforms, one way to ensure that the [Visual Studio Code extension](../tools/code-extension.mdx) uses the same environment as the command-line tools, is to invoke them on the command line. For example:
 
 ```
-$ open -a epoch
 $ code .
 ```
 
-This way, the tools inherit the environment from the shell from which you invoke them. Often, that environment is quite different from what you get if, for example, you invoke the tools by double clicking on their icons.
-
+This way, the tool inherits the environment from the shell from which you invoke it. Often, that environment is quite different from what you get if, for example, you launch the shell from the graphical user interface.

docs/tools/troubleshooting.mdx

@@ -21,6 +21,10 @@ A [video playlist](https://youtube.com/playlist?list=PL4zzL7roKtfXyKE3k8lOwPub9Y
 
 This part briefly describes the background of the project and explains how to get started with the software.
 
+:::warning
+These videos mentioned Epoch, an IDE that is no longer actively maintained. We recommend using our VS Code extension instead.
+:::
+
 **Useful links:**
 
 - [Complete video of part I](https://youtu.be/7vkhX5tS_oI)

docs/tutorial-videos.mdx

@@ -37,7 +37,7 @@ The [regression tests](https://github.com/lf-lang/lingua-franca/tree/master/test
 
 ## Structure of an LF Project
 
-The Lingua Franca tools assume that LF programs are put into a file with a `.lf` extension that is stored somewhere within a directory called `src`. To compile and run the above example, choose a **project root** directory, create a `src` directory within that, and put the above code into a file called, say, `src/HelloWorld.lf`. You can compile the code on the [command line](../tools/command-line-tools.mdx), within [Visual Studio Code](../tools/code-extension.mdx), or within the [Epoch IDE](../tools/epoch-ide.mdx). On the command line this will look like this:
+The Lingua Franca tools assume that LF programs are put into a file with a `.lf` extension that is stored somewhere within a directory called `src`. To compile and run the above example, choose a **project root** directory, create a `src` directory within that, and put the above code into a file called, say, `src/HelloWorld.lf`. You can compile the code on the [command line](../tools/command-line-tools.mdx) or within [Visual Studio Code](../tools/code-extension.mdx). On the command line this will look like this:
 
 ```
     > lfc src/HelloWorld.lf

docs/writing-reactors/a-first-reactor.mdx

@@ -37,7 +37,7 @@ make
 sudo make install
 ```
 
-The above will create a program called `RTI` and install it at `/usr/local/bin/RTI`. Once this program is available in your path, you can compile and execute federated Lingua Franca programs using [Epoch, VS Code, or the command-line tools](/docs/installation). For more details, see the [README file](https://github.com/lf-lang/reactor-c/blob/main/core/federated/RTI/README.md).
+The above will create a program called `RTI` and install it at `/usr/local/bin/RTI`. Once this program is available in your path, you can compile and execute federated Lingua Franca programs using [VS Code or the command-line tools](/docs/installation). For more details, see the [README file](https://github.com/lf-lang/reactor-c/blob/main/core/federated/RTI/README.md).
 
 ## Minimal Example