Update docs for developers to get started.

Also provide an additional .target which allows users to add TM4E to the
current running platform.

Fixes: eclipse-tm4e#107

Signed-off-by: Fabio Zadrozny <[email protected]>

README.md

@@ -34,4 +34,17 @@ Here a sample with TypeScript:
 * **Git**: This `eclipse/tm4e` repository is the reference repository to contribute to `tm4e`
 * **Build and CI**: build can be performed with a simple `mvn clean verify`, continuous integration and deployment is performed by CI jobs at https://hudson.eclipse.org/tm4e
 * **Developers mailing-list**: Contributors are also expected to subscribe the [tm4e-dev mailing-list](https://dev.eclipse.org/mailman/listinfo/tm4e-dev).
-* **Becoming a committer**: as usual with Eclipse.org projects, anyone who's made significant contributions and who 
+* **Becoming a committer**: as usual with Eclipse.org projects, anyone who's made significant contributions and who
+
+## Setting up TM4E for development
+
+After downloading the sources from the github repo, to get the environment, two .target definition files
+are provided at /tm4e/target-platform -- open the selected file inside Eclipse and click
+"Set as Target Platform" (note that this folder isn't configured as a project, so, it has to be
+opened through File > Open).
+
+The `tm4e-target.target` provides a target which allows running TM4E (to be used if you're only
+interested in running TM4E) and `running-platform-plus-tm4e.target`, which provides a target that
+has the current running platform and TM4E (to be used if you are also developing
+other plugins which require the current target platform).
+

target-platform/running-platform-plus-tm4e.target

@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<?pde version="3.8"?><target name="Running Platform + TM4E" sequenceNumber="20">
+<locations>
+<location path="${eclipse_home}" type="Profile"/>
+<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
+<unit id="org.eclipse.license.feature.group" version="1.0.1.v20140414-1359"/>
+<repository location="http://download.eclipse.org/cbi/updates/license/"/>
+</location>
+<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
+<unit id="com.google.gson" version="2.7.0.v20170129-0911"/>
+<unit id="org.jcodings" version="1.0.18.v20170306-1742"/>
+<unit id="org.joni" version="2.1.11.v20170306-1742"/>
+<unit id="org.junit" version="4.12.0.v201504281640"/>
+<repository location="http://download.eclipse.org/tools/orbit/S-builds/S20170306214312/repository/"/>
+</location>
+<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
+<unit id="org.eclipse.platform.feature.group" version="4.7.0.v20170308-2000"/>
+<unit id="org.eclipse.ui.tests.harness" version="1.4.0.v20160830-0648"/>
+<repository location="http://download.eclipse.org/eclipse/updates/4.7milestones/S-4.7M6-201703082000/"/>
+</location>
+</locations>
+<environment>
+<os>win32</os>
+<ws>win32</ws>
+<arch>x86_64</arch>
+<nl>en_US</nl>
+</environment>
+</target>