Simplified chrome.tabs usage.
Add support for changing the branch indexes to bip44 style, *still missing to make pockets hardened* and a reseed mechanism.

Currently new wallets are created with bip44 style (don't do this yet) while old wallets stay with the old scheme.
Make pockets hardened. Will ask for password when creating and mpk gets cached.
Merge branch 'bip44' of https://github.com/darkwallet/darkwallet into bip44