Add Atmel Studio Extension (VSIX) packaging files and scripts.

git-svn-id: http://lufa-lib.googlecode.com/svn/trunk@2529 d5102386-fcda-11dd-9fdb-3debd5008f28
Add transform to update the VSIX extension version automatically when built.

git-svn-id: http://lufa-lib.googlecode.com/svn/trunk@2530 d5102386-fcda-11dd-9fdb-3debd5008f28