Prepare build system for modern cmake (part 1)

To become independent from the FairRoot macros and scripts, simply add the needed macros in cmake/modules and input needed to generate the scripts into cmake/scripts.

Change copied macros such that the input needed to generate the scripts is taken from the local cmake/scripts directory.

Use macros and configuration input from local cmake directory.

Fix problem with removing the existing PATH and LD_LIBRARY_PATH variables when sourcing the config script without additional parameter.