Possibility to add plain xml to idea plugin descriptor
Simplify code (unused modelDescriptor variable)
Merge remote-tracking branch 'origin/master' into 3.1/rcp
Merge remote-tracking branch 'origin/master' into 3.1/rcp

Conflicts:
	plugins/mps-build/languages/build.mps/generator/source_gen/jetbrains/mps/build/mps/generator/template/main/QueriesGenerated.java
Fix typesystem error
Fix missed import and re-generate language
Merge remote-tracking branch 'origin/master' into 3.1/rcp