added translation text string in gui_lite.py

Added gettext _() to the "public key has been copied" text string to be translated.
fixed bug: failed command ``history`` if ``wallet.get_tx_history()`` is empty
create Transaction class
fix the p2sh test
fix p2sh test
add dumpprivkey command; finalize private_keys parameter for signrawtransaction
import ast at the beginning
bugfix: for_sig != -1
Merge pull request #148 from snipsnipsnip/add-translation-string

added translation text string in gui_lite.py
signrawtransaction: parse redeemScript
Merge branch 'master' of github.com:spesmilo/electrum
Merge pull request #149 from polymorphm/tiny-bugfix--history-balance

command ``history`` fail -- if not transactions
add listunspent
Merge branch 'master' of github.com:spesmilo/electrum
move crypto from wallet class to bitcoin.py
simplify get_private_key, use base58
use 4-spaces indentation
fix verify_message calls
store transactions in serialized form
fix: import print_msg