initial electrum formula

fix dependencies for electrum
update armory-qt to 0.90
use python-config --prefix

use python-config --prefix instead of hard coding the paths
Merge pull request #24 from wozz/electrum

electrum 1.9.7
Merge pull request #23 from wozz/master

Update versions libbitcoin, libwallet, obelisk, sx
Merge pull request #26 from wozz/armory-.90

armory-qt 0.90-beta
fix python dependencies for electrum