modules/ims_usrloc_scscf: added DB storage for S-CSCF usrloc
	- currently support NO_DB and DB_WRITETHROUGH
usrloc: remove the filter on nat_bflag for keepalive contact expiration

- keepalives can be sent even for non-natted contacts
- reported by Kristian Kielhofner
async: free the async item after resuming the execution

- reported by Surendra Pullaiah
tm: safety check for uas callid value when callid_matching is 1

- according to the documentation is for UA that cannot match the
  responses when call-id is changed, but is not the case of self
  generated requests
- closes FS#390
pkg/kamailio/deb: init script. Get back SHM_MEMORY PKG_MEMORY and CFGFILE
core/parser: fix loop on broken values matching the prefix of a good value in parse_option_tag_body()

- reported by Savolainen Dmitri, FS#396
topoh: don't encode/decode content for local generated messages

- requests generated by kamailio don't have headers that should be
  hidden
- replies to them don't have anything hidden
- update as part of report from FS#390
topoh: let replies for CANCEL requests be handled

- CANCEL is hop by hop, but can have the call-id hidden when sending out
call_control: Passthrough sip_application

Current patches being submitted to CDRTool and the call_control daemon
allow for SIP application type to be specified. This allows audio or
video services to be rated differently, or even different ratings for
application subtypes (audio.inbound vs. audio.outbound).

This patch allows the sip_application value to be passed through to the
call_control daemon.
kamailio.cfg: catch OPTIONS keepalive requests in route[REQINIT]
Makefile.defs: version set to 4.2.0-dev3
registrar: allow randomization of expire value coming from UA

- new parameter expire_range
- requested in FS#249
registrar: docs updated with expire_range parameter
pkg/kamailio/deb: update changelog files to dev3 version
modules/ims_usrloc_scscf: incorret assignment that causes incorrect shm free on pkg_malloc'd memory
pdb: remove internal reference, pointed out from Carsten Bock
pdb: move gitignore to own directory
pdb: remove pdb from global gitignore
pdb: add debian init file
mtree: reset tree statistics upon reload

- related to FS#398, reported by JoshE