Update for version 2.0.0_2
Basic async commit

This code isn't guaranteed to work, but it doesn't break other stuf..
Clean up encoder/decoder settings

This moves the settings over to Couchbase::Settings instead.
GH-19: add missing MANIFEST files
GH-17: Use newSVpvn_share

This is available since Perl 5.7
GH-18: Unify codepaths for FMT_RAW and unrecognized flags