defined a new specific RELEASE permission which is distinct from the sta...

...ndard BUILD permission. This allows to fine tune access permissions: not all users allowed to trigger a build should be allowed to trigger a release build.

Note: This commit introduces a breaking change since upgrading to a newer plugin version including this feature will automatically revoke release permissions from existing users (they'll just be able to build, not release). Admins will have to grant the release permissions back again.