res_pjsip: Enforce requirements for session timer minimum expiration period and normal expiration period.

This change enforces the requirements in PJSIP for session timer configuration. The minimum
expiration period must be 90 seconds or higher and the normal expiration period can not
be lower than the minimum expiration period. If either of these were done the code would
assert at session setup time.

ASTERISK-24336 #close
Reported by: Leon Rowland


git-svn-id: http://svn.asterisk.org/svn/asterisk/branches/12@427978 f38db490-d61c-443f-a65b-d21fe96a405b
chan_motif / chan_pjsip: Fix incorrect "No such module" messages when reloading.

For chan_motif the direct return value of the underlying config options framework
was passed back. This can relay various states which the module loader would not
interpet as success. It has been changed so only on errors will it report back
an error.

For chan_pjsip the code implemented a dummy reload function which always
returned an error. This has been removed as all configuration is held within
res_pjsip instead.

ASTERISK-23651 #close
Reported by: Rusty Newton


git-svn-id: http://svn.asterisk.org/svn/asterisk/branches/12@427981 f38db490-d61c-443f-a65b-d21fe96a405b