Fixed qi::alternative test code.
Made alterative_function functor const to match non-specialized version.
Removed some unnecessary namespacing aliasing in tests.
Merge pull request #12 from vtnerd/bugfix/qi_tests

Bugfix/qi tests
moved (variant)has_substitute and (variant)find_substitute into traits
Fix for case where a single-element sequence is not being moved into a variant that can accept it.
cleanup
added mising files
various sequence handling fixes
Merge branch 'develop' of https://github.com/boostorg/spirit into develop