Call recording encoder/format choice 2/3

Adds a user option between WB AMR (the default) or HE-AAC for the encoding of call recording audio. Also changes the output format of the file appropriately (WB AMR now uses the WB_AMR output format and HE_AAC chooses the MPEG_4 output. File extensions are adjust accordingly as well).
This was in reponse to people complaining the quality of call recording audio is poor. It's noticibly better using HE-AAC, but filesizes are larger.

Change-Id: I31f4a57042cf9e221ea2292922f071c955170e1e