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#### Description **Use origin-host of CCR response as destination-host of subsequent CCR requests** When connecting to a diameter node which using relay, it may load balance requests to multiple servers for handling. This change ensures that subsequent requests are sent to the same server.

**Honour AVP_Time_Quota_Threshold in CCR response** Charging server indicates it want an interim update X number of seconds before all quota has been used.

**Add new modparam «strip_plus_from_e164»** The existing formatitng routine check if it's a tel: or sip: uri, and sets E.164 or SIP according to that. If it's E.164, it strips "tel:" too. A subscription id with leading "+" is actually of type SIP.

I didn't want to make a breaking change here, so I introduced a new setting which fixes the behaviour.

**Moved subscription id formatting into a common function** For more clean code, and one place to make further adjustments.

**Handle CCR response without AVP_Validity_Time** If missing, various places in the module reported immediate expire.

**Handle IMS_RAR (Re-auth) request from charging server** Typical scenario is that there's a missing interim update, and the server want to check if the session is still alive. At reception we try a lookup and if found, schedule a new request.

**Handle IMS_ASR (Abort) request from charging server** Similar handling as for re-auth, but for server-initiated termination of the call.

**Fixed issue with signed/unsigned int related to check for Expires header** cscf_get_expires_hdr() returns signed (-1 for not found), while that value was added to the outgoing diameter request unsigned. That again resulted in an Expires AVP with a really large value, and was rejected by the charging server.

Most probably cscf_get_expires_hdr() should be changed to return unsigned since the value theoretical can be that big, but since that is a common function for the ims modules it would require more testing than I'm capable of right now.

**Use str_dup() and str_free() from ims_getters instead of locally defined** Those were needed more places.