Encode body even if charset doesn't match case
Encode body even if charset doesn't match case

As long as the charset is a known one according to Ruby's matching algorithm (which appears to be case insensitive and also includes aliases), we should use that encoding.

Fixes #542 (and maybe #541 as well)

jnunemaker/httparty,jnunemaker/httparty,jnunemaker/httparty