Contrib: Introduce script to tag compiled binaries for convenience (py)

[jtimon]

I felt I needed to incorporate something like this to my workflow. If it is not useful for bitcoin, I'm happy to propose it on elements, freicoin or just keep it to myself. Still putting it here just in case.

Example usage (with the appropriate bitcoin/.git/config):

git fetch origin
git checkout origin/v0.12.0
make check -j21
python contrib/devtools/tag-binaries.py v0.12.0

git checkout origin/master
make check -j21
python contrib/devtools/tag-binaries.py master

# Non-bitcoin examples:

git fetch elements
git checkout elements/alpha
make check -j21
python contrib/devtools/tag-binaries.py alpha

git checkout jtimon/jt
make clean
make check -j21
python contrib/devtools/tag-binaries.py jt

git fetch freicoin
git checkout freicoin/master
git clean -fdx
./autogen.sh
./configure
make check -j21
python contrib/devtools/tag-binaries.py freicoin

git fetch elements
git checkout elements/pre-gamma
git clean -fdx
./autogen.sh
./configure
make check -j21
python contrib/devtools/tag-binaries.py pre-gamma

[jtimon]

Sorry, wrong opened tab...