FindQt4: Make AUTOMOC work regardless which order Qt 4/5 is found.

Commit 321e348e (QtAutogen: Use Qt 4 IMPORTED targets to find
executable locations., 2014-01-24) attempted to fix this problem,
but only solved it for a particular ordering of find_package for
Qt 4 and Qt 5.

Add a test to ensure that it works with both orderings.
OS X: Make sure RPATHs are unique to avoid possible corruption.

When using link_directories() and including CMAKE_CFG_INTDIR,
one can end up with duplicate RPATHs in the binary which
install_name_tool cannot fix without corrupting the binary.
Also, the cmake_install.cmake file has been fixed to correctly
handle these generator specific variables.
QtAutogen: Make uic work even when the source is in a subdir.

Modify the includedUis to store the path to the file which includes
the ui file. Reuse that path to generate the output file from the
uic process.
Merge topic 'osx-rpath-unique'

028a5285 OS X: Make sure RPATHs are unique to avoid possible corruption.
Merge topic 'fix-Qt-autogen'

6053ce22 QtAutogen: Make uic work even when the source is in a subdir.
1fc9ecfa FindQt4: Make AUTOMOC work regardless which order Qt 4/5 is found.