fix LaunchServices database search under Mac OS X 10.7

add MUnit support
add J/Link support
add DocumentationBuild support

fix debug output

fix bug in launch services database search code under Mac OS X

* preserve user defined overrides upon option initialization
* don't set RUN_SERIAL option in Mathematica_SET_TESTS_PROPERTIES

* fix cache cleanup bug
* use functions instead of macros to work around Windows backslash
problem
* improve Mathematica_ADD_CUSTOM_TARGET documentation

* properly document SYSTEM_ID option
* stricter Mathematica version checks
* fix bug in Mathematica_EXECUTE with handling of SYSTEM_ID option

* Windows registry search fix
* add work-around for Windows cmd.exe quotation problem
* fix bug in function that sets up version variables
* make code more robust against exceptional usage cases

add Mathematica_ENCODE function
add Mathematica_ABSOLUTIZE_LIBRARY_DEPENDENCIES function
fixed use of Mathematica_USERBASE_DIR in examples
fixed RPATH issues under Linux

* option initialization fixes
* tested with Mathematica 8.0.4