The test_case_template.hpp header is deprecated in Boost, and the
latest Boost version is now throwing warnings during the build.
In Boost 1.59 (at least), this header is included transitively by the main
Boost test header, so this header is not needed by any supported Boost
version.
Previous test strings did not utilize extended table unicode, so some
cases slipped through testing. When initializing wxString, we need to
be careful to specify that we are initializing from a UTF-8 string
otherwise the system will utilize a locale-specific initialization.