Fixing project after the wrong stash pop-up

Updated the MTT to use a series of commands and no recustion
Renamed to PL14
Fixed strip whitespace bug
Fixed append bug and performance
Updated benchmark setup
Fixed Text.deleteRight
Renamed Text.deleteRight to Text.dropRight
Merge branch 'feature/PL14' into develop

Conflicts:
	examples/fr.unice.i3s.sigma.examples.pl14.acceleo/tasks/OO2Java.xml
	examples/fr.unice.i3s.sigma.examples.pl14/META-INF/MANIFEST.MF
	plugins/fr.unice.i3s.sigma.docgen/src/fr/unice/i3s/sigma/docgen/common/ClassDiagram.scala
	plugins/fr.unice.i3s.sigma/src/fr/unice/i3s/sigma/m2t/AbstractTextTemplate.scala
	plugins/fr.unice.i3s.sigma/src/fr/unice/i3s/sigma/m2t/Decorators.scala
	plugins/fr.unice.i3s.sigma/src/fr/unice/i3s/sigma/m2t/M2T.scala
	plugins/fr.unice.i3s.sigma/src/fr/unice/i3s/sigma/m2t/StaticTextTemplate.scala
	plugins/fr.unice.i3s.sigma/src/fr/unice/i3s/sigma/m2t/Text.scala
	plugins/fr.unice.i3s.sigma/src/fr/unice/i3s/sigma/support/EMFScalaSupport.scala
	plugins/fr.unice.i3s.sigma/src/fr/unice/i3s/sigma/workflow/lib/GenerateEMFScalaSupport.scala
	tests/fr.unice.i3s.sigma.tests/src/fr/unice/i3s/sigma/m2t/TextSpec.scala