Add sip.conf

This makes it so chan_sip won't monkey with chan_pjsip for normal testing.
If we want to do chan_sip testing, we at least have it available.
Initial install shell script addition

This will configure and build pjproject correctly, and install Asterisk
configs. Eventually it should also build Asterisk.
Update PJSIP

Add some endpoints (1000-1019)