Adapted code for compilation of Qt on OS X 10.7 - 10.9.

CASH-qt.pro: Changed comment block for windows into a proper conditional block.
Added example for INCLUDEPATH and some examples for QMAKE_CXXFLAGS.

readme-qt.rst: Added instructions for less painful build with QT Creator

net.cpp: Fixed ambiguous namspace for array.

Added bitcoin.icns for OS X icons.

Fixed 32 bit alignment to 16 bit alignment for OS X 10.9, which
seems to reject 32 bit alignment.

Fixed ambigous namespace for insert method.