First attempt at version application script

First attempt at version application script

Usage:
Create/Checkout new branch
    AKA, #.#-beta# or #.#.#
Run build/tools/apply_version.sh
git commit -as to save changes.

Can be told what version to use instead via first command line option.
Uses current branch name for "HeadURL" and auto-version checks.

Signed-off-by: Thomas Berezansky <tsbere@mvlc.org>