NPE fix
Merge branch 'master' of https://github.com/metaborg/spoofax-modelware

Conflicts:
	org.spoofax.modelware.gmf/src/org/spoofax/modelware/gmf/EditorPairUtil.java
Initial documentation.
Moved documentation to 'doc' repo.
Added maven pom.xml files.
Fix wrong relative path.
Update gitignores
Update gitignore
Remove unused dependency
Fixes for two-stage build and cleanup.
Made strj and the generator Java projects. Remove dependence on strategoxt.jar for everything.
Add project metadata to POM files, required for publishing to the Maven central repository.
Use text-reconstruction strategy from runtime libraries instead.
Make sure that Eclipse plugins are not installed and deployed.
Don't skip installation and deployment, not required.
Use a qualifier version, so that it can be deployed multiple times.
Bump version to 1.3.0-SNAPSHOT
Merge branch 'master' into spoofax-release