add icons to "New..." and "Copy to clipboard" buttons

doc/assets-attribution.txt

@@ -27,7 +27,8 @@ License: You are free to do with these icons as you wish, including selling,
  copying, modifying etc.
 
 Icon: src/qt/res/icons/configure.png, src/qt/res/icons/quit.png,
-      src/qt/res/icons/editcopy.png, src/qt/res/icons/editpaste.png
+      src/qt/res/icons/editcopy.png, src/qt/res/icons/editpaste.png,
+      src/qt/res/icons/add.png
 Designer: http://www.everaldo.com
 Icon Pack: Crystal SVG
 License: LGPL

src/qt/bitcoin.qrc

@@ -21,6 +21,7 @@
         <file alias="receiving_addresses">res/icons/receive.png</file>
         <file alias="editpaste">res/icons/editpaste.png</file>
         <file alias="editcopy">res/icons/editcopy.png</file>
+        <file alias="add">res/icons/add.png</file>
     </qresource>
     <qresource prefix="/images">
         <file alias="about">res/images/about.png</file>

src/qt/bitcoingui.cpp

@@ -82,8 +82,10 @@ BitcoinGUI::BitcoinGUI(QWidget *parent):
     
     QPushButton *button_new = new QPushButton(tr("&New..."));
     button_new->setToolTip(tr("Create new receiving address"));
+    button_new->setIcon(QIcon(":/icons/add"));
     QPushButton *button_clipboard = new QPushButton(tr("&Copy to clipboard"));
     button_clipboard->setToolTip(tr("Copy current receiving address to the system clipboard"));
+    button_clipboard->setIcon(QIcon(":/icons/editcopy"));
     hbox_address->addWidget(button_new);
     hbox_address->addWidget(button_clipboard);