Add audio modem integration for transaction sending & receiving

http://www.flaticon.com/free-icon/speaker-outline_54951

Speaker icon made by <a href="http://catalinfertu.com" title="Catalin
Fertu">Catalin Fertu</a> from <a href="http://www.flaticon.com"
title="Flaticon">www.flaticon.com</a> is licensed under <a
href="http://creativecommons.org/licenses/by/3.0/" title="Creative
Commons BY 3.0">CC BY 3.0</a>

http://www.flaticon.com/free-icon/mic_10032

Microphone icon made by <a href="http://www.elegantthemes.com"
title="Elegant Themes">Elegant Themes</a> from <a
href="http://www.flaticon.com" title="Flaticon">www.flaticon.com</a> is
licensed under <a href="http://creativecommons.org/licenses/by/3.0/"
title="Creative Commons BY 3.0">CC BY 3.0</a>

gui/qt/qrtextedit.py

@@ -1,4 +1,5 @@
 from electrum.i18n import _
+from electrum.plugins import run_hook
 from PyQt4.QtGui import *
 from PyQt4.QtCore import *
 
@@ -25,6 +26,7 @@ class ShowQRTextEdit(QRTextEdit):
         super(ShowQRTextEdit, self).__init__(text)
         self.setReadOnly(1)
         self.button.clicked.connect(self.qr_show)
+        run_hook('show_text_edit', self)
 
     def qr_show(self):
         from qrcodewidget import QRDialog
@@ -49,6 +51,7 @@ class ScanQRTextEdit(QRTextEdit):
         if win:
             assert hasattr(win,"config"), "You must pass a window with access to the config to ScanQRTextEdit constructor."
         self.button.clicked.connect(self.qr_input)
+        run_hook('scan_text_edit', self)
 
 
     def qr_input(self):