CMake: Only use internal boost header (if available) for regression check

Fix a regression where a test for an icc regression in
check_01_cxx_features.cmake incorrectly used a generic <boost/signals2/...>
include. Such an include file doesn't have to be available at this early
point in the configuration run. User internal boost headers (if available)
instead - otherwise just test nothing.
Merge pull request #184 from tamiko/fix_cxx_test

CMake: Only use internal boost header (if available) for regression check
Allow querying whether a DoF is located on a vertex, line, etc.
Merge pull request #153 from bangerth/query-dof-associations

Allow querying whether a DoF is located on a vertex, line, etc.
CMake: Remove test DEAL_II_HAVE_CXX11_ICCBOOSTSIGNALSBUG_OK

We cannot sanely test for this regression prior to boost setup. And after
boost setup it is incredibly ugly to do so because DEAL_II_WITH_STDCXX11 is
already processed.
CMake: Bugfix: Also sanitize (cpp) macros in enable_if_links
Merge pull request #185 from tamiko/fix_cxx_test

Fix cxx test