Repeated code: `CreateConverter`

[Vipul-Cariappa]

There are two overloads to CreateConverter.
First:

CPyCppyy/src/Converters.cxx

Line 3327 in 482ccb7

CPyCppyy::Converter* CPyCppyy::CreateConverter(const std::string& fullType, cdims_t dims)

Second:

CPyCppyy/src/Converters.cxx

Line 3538 in 482ccb7

CPyCppyy::Converter* CPyCppyy::CreateConverter(Cppyy::TCppType_t type, cdims_t dims)

One takes a string and the other a type (clang::QualType). But the type version again converts the type to a string and processes it in the same way as the string version.
Look:

CPyCppyy/src/Converters.cxx

Lines 3538 to 3558 in 482ccb7

	CPyCppyy::Converter* CPyCppyy::CreateConverter(Cppyy::TCppType_t type, cdims_t dims)
	{
	// The matching of the fulltype to a converter factory goes through up to five levels:
	// 1) full, exact match
	// 2) match of decorated, unqualified type
	// 3) accept const ref as by value
	// 4) accept ref as pointer
	// 5) generalized cases (covers basically all C++ classes)
	//
	// If all fails, void is used, which will generate a run-time warning when used.
	// an exactly matching converter is best
	std::string fullType = Cppyy::GetTypeAsString(type);
	ConvFactories_t::iterator h = gConvFactories.find(fullType);
	if (h != gConvFactories.end()) {
	return (h->second)(dims);
	}
	// resolve typedefs etc.
	Cppyy::TCppType_t resolvedType = Cppyy::ResolveType(type);
	const std::string& resolvedTypeStr = Cppyy::GetTypeAsString(resolvedType);

Proposal: We should remove the string overload. The string parsing can stay for now. String parsing - to be removed eventually.