Metadata: get_client_names_by_* fixes

Fixed long lines.

Improved efficiency by avoiding multiple loops over the same data.
SSLServer: Removed decode_request_content call

decode_request_content() just adds support for gzipped content, which
the Bcfg2 client doesn't support.  Given that this feature was only
added in Python 2.7, it's unlikely we'll be adding support for gzipped
POST content any time soon.