show/raise install dialog

make sure install dialog doesn't show up behind other windows when
electrum is started
replaced jackjack encryption with corrected ecies implementation
in ecies encryption, mac headers+ciphertext instead of just ciphertext
Merge pull request #704 from badmofo/ecies-encryption

replaced jackjack encryption with corrected ecies implementation
Remove Bitcoin address from serialized encryption format. Enable encrypt commands, fix ser_to_point() and add some tests
Merge pull request #703 from wozz/install-show

show/raise install dialog
fix #682
Merge remote-tracking branch 'upstream/master'