support windows-1258
use encoding constants
parse non-ascci filenames
Loosen Travis-CI ruby versions; fix 1.9.2 not installable
Merge pull request #767 from zendesk/grosser/Windows1258

support windows-1258
Merge pull request #769 from zendesk/grosser/encoding

Prefer encoding constants to strings: `Encoding::UTF_8` vs `'utf-8'`
Merge pull request #770 from bf4/ruby192

Loosen Travis-CI ruby versions; fix 1.9.2 not installable
Merge pull request #762 from zendesk/grosser/content-utf8

parse non-ascci filenames
skip 1.9.2