Update Qt4 SCons tool from upstream and add the Qt5 SCons tool.
Use pre-computed boolean flags.
Add qt5 SCons tool.
Wrap qt5-enabled check in a helper.
Use the right qrc based on the Qt version.
Check for Qt5Core >= 5.0 on Linux when qt5 is enabled.
Add method for getting the correct uic builder.
Use the right uic.
Hm, actually enabling both tools conflicts. Use ARGUMENTS to get the qt5 flag before the environment is created.
Make Qt5 binaries obey verbose setting.
Use the right UIC.
No need to explicitly call qrc on the .qrc file.
Fully depend on the Qt5 SCons tool on Windows and Linux. The Qt4/Qt5 tool for OS X doesn't work with framework builds of Qt which is why the custom logic is still there. We should submit our custom changes upstream so we can remove these.
Update qt4/qt5.py from upstream to include MOC COMSTRs.
Update Qt COMSTRs.
Oops, missed ifdef'ing a use of reportAdditionalMemoryCost based on Qt version.
Don't append result of UIC on the .ui files to sources.
Some code cleanup, while working on Library concurency refactoring.

Thanks to Daniel for preparing this patch!
Merge pull request #89 from troyane/CodeCleanup

Some code cleanup, while working on Library concurency refactoring.