Don't set the decoder framerate to the maximum

Ignore-this: 68e6ecb901bb93515422fa9fcaaa2c83

Start at a low framerate of 10, because PJSIP will adjust the clock based on the
detected frame rate

darcs-hash:20140922161327-56b4d-73b3a307c80551a0bf7d8225597418c34d55b729
pjsip: support BGRA format in the AVFoundation backend

Ignore-this: de90116e5742393a0a9982d0b2a0b7f9

darcs-hash:20140923131857-56b4d-8494e12b38bc34efe353449632594d882064ffdb
pjsip: fixed opening device in VGA resolution in AVFoundation backend

Ignore-this: ad4851deef60dc6e59219d2ea9f5ba98

Looks like more settings need to be specified than those specified in the
Apple documentation.

darcs-hash:20140923132026-56b4d-cc5f32b432b7e69eacc38fb2882df902a6e665db
pjsip: AVFoundation: fix processing frames when camera is in use

Ignore-this: 42154f4e86688eac1e302459e34e02bd

darcs-hash:20140923151137-56b4d-76657a67f5c2b2b5f6b3d4c7da73b387ac40c6a6