Do not recurse through /usr/include when collecting sub-includes.

This repreatedly confuses rmkdepend () for no real value. A typical error:
warning: defined __cplusplus && (__cplusplus >= 199711L || __GNUC_PREREQ (4, 4))
Fix the dictionary for core/textinput and gui/gui (CMake). Responsible for the failure of test roottest-root-meta-execTypedefList-auto
Fix for ROOT-6546 (ctest: generate a rootmap with a library name compatible with roottest)
Also print structs; add test.
Resolve #27: Fix --with-workdir switch in CPT
Close #30: Implemented overrides for LLVM, Clang, and Cling repos
Close #35: Fix typo in Cling executable name
Remove temporary DMG and staging directories
Close #38: Implement switches --dmg-tag and --last-stable=dmg
Add --dmg-tag to argument parser configuration
Close #39: Implement --no-test switch to skip the test suite
Use the downloaded CMake binaries in Windows
Accept relative paths in --with-workdir switch
Resolve #36: Handle output of 'where' command correctly
The new driver doesn't take default image name.
llvm::errc::success got changed to llvm::errc::no_such_file_or_directory.
Follow the updates in clang's BackendUtil, from where we copied our BackendPass.
Replace createMainFileID with the new interface.
Use the shortcut to create the ASTContext.
ExprResult::take -> ExprResult::get, ExprResult::takeAs -> ExprResult::getAs.