ObjectMixin: nearly not measurable optimizations
travis: code-checker checks whole repository
Html: floats in attributes are printed in natural notation [Closes nette/forms#50]
Strings::substring(): unified behavior when both start and length are negative

behavior of iconv_substr is inconsistent with mb_substr (http://3v4l.org/JvOlj)
Strings::toAscii(): unsupported characters are removed instead of being replaced with '?'

Conflicts:
	tests/Utils/Strings.toAscii().phpt
Strings: added tests for few more UTF-8 edge cases
typo