Bundle fixes

When trying to use the BundleUtilities in a non-standard environment (e.g. cross-compilation) various bugs were found which are fixed by this MR:

• install_name_tool was used verbatim although CMAKE_INSTALL_NAME_TOOL exists
• otool -D was called instead of using the find_programed one which fails if it isn't in the PATH
• verbose of get_prerequisites could not be enabled -> Added a global variable for that
• Prefixed tools (e.g. x86_64-pc-linux-gnu-ldd) could not be used -> Check only last part of name
• Scripts where passed to get_prerequisites by BundleUtilities if they were executable which caused a hard error. This is critical when wrapper scripts are the entry point of an OSX app Bundle as there was no way NOT to check that. -> Fixed in a lower level at GetPrerequisites which checks for .sh/.bat extension or shebang (!# at start of file). See also #18667 (closed)