Second attempt to get optimal translation paths when codec_resample is used.

Second attempt to get optimal translation paths when codec_resample is used.

This borrows code heavily from changes made in translation code in Asterisk 10.
This uses the quality and sample rate change of translation in order to pick
paths rather than the computational cost of translations. Computational cost
is used solely in determining if a single translation step from a specific
translator is better than the same translation step provided by a different
translator.

(closes issue ASTERISK-16821)
reported by Andrew Lindh

Review: https://reviewboard.asterisk.org/r/1772

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@357760 65c4cc65-6c06-0410-ace0-fbb531ad65f3