Update F# guidance

The current docs install FSAC as a global tool, but invoke it as a local tool. Invoking it as a global tool means executing the globally-installed shim (which is installed to a global path by default).

Author: baronfel

docs/src/language_servers.md

@@ -129,7 +129,7 @@ Follow installation instructions on [LSP-elm](https://github.com/sublimelsp/LSP-
         "clients": {
             "fsautocomplete": {
                 "enabled": true,
-                "command": ["dotnet", "fsautocomplete", "--background-service-enabled"],
+                "command": ["fsautocomplete", "--background-service-enabled"],
                 "selector": "source.fsharp",
                 "initializationOptions": {
                     "AutomaticWorkspaceInit": true
@@ -139,6 +139,9 @@ Follow installation instructions on [LSP-elm](https://github.com/sublimelsp/LSP-
     }
     ```
 
+!!! info "A note about .NET Tools and $PATH"
+    If the `fsautocomplete` executable isn't on your $PATH after installing it globally, ensure the .NET global tools location (by default `$HOME/.dotnet/tools`) is on your $PATH.
+
 ## Fortran
 
 1. Install the [ Fortran](https://packagecontrol.io/packages/Fortran) package from Package Control for syntax highlighting.