Add additional type to allow for types themselves to be declared deprecated (through using statements and the like).
fix tautological compare error
Fix implicit conversion warnings for getter.
std::size_t for life.
Clang's silly tautological error can die in a fire. D:<
Change `userdata` to `usertype` names.
We don't need to make the function names
`open_usertype` now, since `new_usertype`
makes sense.
Headerguard derp; fixed.
Proper deprecation to alert users to API name changes.
Use 2 string types to properly filter bad name-based usertype overloads.
Merge branch 'api-fix' of github.com:ThePhD/sol into api-fix