use nunicode for proper to_upper/to_lower string conversions
add <cstring> for std::memset
Merge branch 'master' into nunicode

Conflicts:
	configure
	styles
increase buf to hold trailing '\0' + better names
Merge pull request #530 from mapbox/nunicode

use nunicode for language aware to_upper/to_lower string conversions
cleanup after 195560090/#309/#530
fix 'run-linux' target - refs #534/#511
merge with master