noticed keypad binds were named like this in SE (probably due to using the names given by SDL there) and it's nicer anyway. better do this sooner than later.
On Linux and macOS, using Clang to compile OpenStarbound produces about 400 MB worth of warnings during the build, making the compiler output unreadable and slowing the build down considerably.
99% of the warnings were unqualified uses of std::move and std::forward, which are now all properly qualified.
Fixed a few other minor warnings about non-virtual destructors and some uses of std::move preventing copy elision on temporary objects.
Most remaining warnings are now unused parameters.
