Retains the unnamed register during jumps
Adds eventhandler to restore the unnamed register
Escapes the cached string
Adds a test for the new feature
Merge branch 'retaining_the_unnamed_register' of git://github.com/LFDM/ultisnips into LFDM-retaining_the_unnamed_register
Try hard to retain the unnamed register. Patch by Gernot Höflechner - LFDM.