Localization: French: Improvement of translation
JabRef_2.10 loc-ru (v0.0)

1. Strings translated 100%:
- IntegrityMessage_ru.properties
- JabRef_ru.properties
- Menu_ru.properties

2. Init. installer_language-ru:
- russian.nsh

Comments/remarks are welcome!
Updates comment in header of setup.nsi and updates GPL hint to version 3
Enables Russian as installer language on Windows
Enables Russian translation
Menu entry for "Find unlinked files" now re-uses translation for dialog title.
Merge branch 'beta_2.10'

Conflicts:
	jabref/src/resource/JabRef_fr.properties
	jabref/src/resource/JabRef_ru.properties