Fix OS X issue: window start in foreground

When run from command line, the window starts behind all other windows.
raise_() will bring the window to the front.
multisig accounts: sort pubkeys
fix: getpubkey
account:simplification
account:simplification
add optional default value to text dialog
get_pubkey_from_x
sort signatures for multisig
fix and simplify tx serialization
re-enable seed tests. get_public_keys method
check seed in gui. fixes #622
Merge pull request #644 from wozz/raise_window

Fix OS X issue: window start in foreground
broadcast tx in a separate thread
rename do_send as send. fixes #645
hooks and workflow for 2of3 wallets
remove hardcoded seed
don't change default_wallet_path
transaction: add_signature(), is_complete() methods
Merge branch 'master' of github.com:spesmilo/electrum into clean
fix: public instead of private