Add a way to directly detect Constructor and Destructor (and convertor)

Add TFunction::ExtraProperty (and TClingMethodInfo::ExtraProperty)
and the enum values:
   kIsConstructor
   kIsConversion
   kIsDestructor

[The set of values use for Property, see TDictionery EProperty
uses all 32 bits of the typical enum underlying storage]
Reimplement GetUserHomeDirectory().
Update header name.
Update header name.
Options moved to llvm; CI->createDiagnostics; Path
Revert clang::Decl::ClearLinkageCache() patch; implement here instead.
Non-MC JIT does not support exception handling anymore.
Options moved from clang to llvm.
Header renamed.
Use StringRef instead of Path.
Use StringRef instead of Path.
File magic moved / changed.
Fix include.
Rmove invalud / unused fwd decl of Path.
Fix small string / $HOME mess.
New DeduceAutoType() interface.
Remove more Paths.
Updated signature.
Header renamed.
Fix hack.