C++: Revert problematic template specialization changes

This mainly reverts

    commit 81721f67
    C++: Fix resolving of recursive typedef

    commit 2070431d
    C++: Fix resolving of partial specialization

and some bits of other changes due to dependencies. It also reverts

    commit e0594fc9
    C++: Fix expensive lookup for boost

which attempted to solve the upcoming problems.

Task-number: QTCREATORBUG-14741
Task-number: QTCREATORBUG-14889
Task-number: QTCREATORBUG-14962
Change-Id: I3f9e1f97199e5199b71da394fc27051c7709bd1f
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>