* #6935 Updated documentation for requirements (#7669)

* Fixed first line of war installation

Author: offtherailz

docs/developer-guide/requirements.md

@@ -1,23 +1,37 @@
 # Requirements
+
 In this section you can have a glance of the minimum and recommended versions of the tools needed to build/debug/install MapStore
 
 ## War Installation
 
-You can download a java web container like Apache Tomcat from [here](https://tomcat.apache.org/download-70.cgi) and install it.
+You can download a java web container like *Apache Tomcat* from and *Java JRE*
 
-You will also need a Java [JRE](https://www.java.com/it/download/)(minimum version: 8)
+| Tool   | Link                                               | Minimum | Recommended | Maximum       |
+|--------|----------------------------------------------------|---------|-------------|---------------|
+| Java   | [link](https://www.java.com/it/download/)          | 8       | 9           | 11¹           |
+| Tomcat | [link](https://tomcat.apache.org/download-80.cgi)  | 8.5     | 9           | 9¹            |
 
 ## Debug / Build
 
-These tools needs to be installed:
-
-| Tool | Link | Minimum | Recommended | Deprecated |
-|---|---|---|---|---|
-| npm | <a href="https://www.npmjs.com/get-npm" target="_blank">link</a> | >= 5 | >= 6 | |
-| NodeJS | <a href="https://nodejs.org/en/" target="_blank">link</a> | >= 10 | >= 12 | <10 |
-| mvn | <a href="https://maven.apache.org/download.cgi" target="_blank">link</a> | >= 3.1.0 | >= 3.6 | |
-| python | <a href="https://www.python.org/downloads/" target="_blank">link</a> | >= 2.7.9 | >= 3.7 | |
-
-Python is only needed for building documentation.
-
-If you are using Node >= 12 you can remove the -max_old_space_size=2048 config for the compile *script*
+These tools needs to be installed (other than **Java** in versions above above):
+
+| Tool       | Link                                                       | Minimum | Recommended | Maximum     |
+|------------|------------------------------------------------------------|---------|-------------|-------------|
+| npm        | [link](https://www.npmjs.com/get-npm")                     | 5       | 6           | 6.14.13²    |
+| NodeJS     | [link](https://nodejs.org/en/")                            | 10      | 12          | 14.17.0²    |
+| Java (JDK) | [link](https://www.java.com/en/download/help/develop.html) | 8       | 9           | 11¹         |
+| Maven      | [link](https://maven.apache.org/download.cgi")             | 3.1.0   | 3.6         |             |
+| python³    | [link](https://www.python.org/downloads/")                 | 2.7.9   | 3.7         |             |
+
+!!! notes
+    Here some notes about some requirements and reasons for max version indicated, for future improvements and maintenance :
+
+    - ¹ About Java and Tomcat
+        - For execution tested on Java v11.
+        - Build with success with v11, only smoke tests passing on v13, errors with v16.(Details on issue [#6935](https://github.com/geosolutions-it/MapStore2/issues/6935))
+        - Running with Tomcat 10 causes this issue [#7524](https://github.com/geosolutions-it/MapStore2/issues/7524).
+    - ² About NodeJS and NPM:
+        - NPM 7 not supported yet.
+        - NPM 6.14.15 causes [this issue](https://github.com/geosolutions-it/mapstore-project/issues/18) on MapStore project system. No other know issues.
+        - *If you are using Node >= 12 you can remove the -max_old_space_size=2048 config for the `compile` script*
+    - ³ Python is only needed for building documentation.