CB-6814 Add license to CONTRIBUTING.md
adding browserify option
CB-6919 help should list windows8 as an available platform, and not wp7
CB-6931: Fix licence headers in plugman
Update cordova-lib dependency to 0.21.4
Grr. Update cordova-lib dependency to 0.21.5
CB-6930: Updated version and RELEASENOTES.md for release 0.22.3