core: fixed bug in PV caching that broke the use of the $$ symbol

- Found and fixed by Hugh Waite @ Crocodile RCS
(cherry picked from commit c059041a71a1b7175243c366316108ce370fffa7)
siputils: fix decode2format fuction to handle ; in userpart

- backported from ff22a1cbc2b817d63611b3da967d8245e11cb84c
json: proper handling of empty values for json documents
(cherry picked from commit 15e1ae6720136a698326a0b53f6db8eef73e3e5a)
core: end simple pv name (e.g., $xy) at end of line

- cfg parser was throwing error if last token in a line was $xy as pv
  with \n was not found
(cherry picked from commit d2d6b4b932c7df6e6620a256692be5ef049356a3)
modules/sqlops: Check if pv_spec is available before trying to use it.

Instead of segfaulting when the script writer has not specified enough PV
specs to hold all the query's result columns, bail out with an error message.
- backport of a21750ff6fcf87d8e3f54597bdd3f1171846e6cb
pua_reginfo: fix setting lengths of contact attributes

- fix also for warning from FS#255 reported by Ovidiu Sas
- backport from f76bd09d4800ea63552c11002d7f6f72569e78ed
msilo: safety check for freeing tmp_extra_headers

- it can be a static empty buffer
- reported by Stoyan Mihaylov
- backport of 23b84739a72c5cca1fd397fbe1a7468a621cc2e6
msrp: return proper value for $msrp(code)

- internally there is an offset of 10000 to the value in the msrp reply
- reported by Peter Dunkley
(cherry picked from commit 1690eafbb599842f0507ad41c1590fcbba8c7630)
core: dns - prevent queries for IPv4/6 address literals

- prevent A queries for IPv6 address literals or AAAA queries for IPv4
  address literals
- patch by Simon Perreault
(cherry picked from commit 9e6f0268097d81c0e06c7fe33599d0763ed38179)
kamailio.cfg: fixed typos to speeddial

- backport of 0fd954bc6a8f94ac5e8087f6b8abdba372505c6e
app_python: Bugfix for rewrite_ruri (backport from 4.x)

*) Fixed a bug in msg_rewrite_ruri discovered by "V Tone" <vtone001@gmail.com>.
*) Removed 'python exception' when do_action returns error. Reason: it is not an exception.
*) Removed abort() if first_line type is invalid.
pkg: version set to 3.3.4 for rpm specs
pkg: version set to 3.3.4 in deb specs
Makefile.defs: version set to 3.3.4
ChangeLog: updated for release of v3.3.4
pkg/kamailio/(centos|fedora): updated ver in .spec
rtpproxy: fix spelling error in docs, reported from Victor V. Kustov, coyote at bks dot tv
(cherry picked from commit a0b01f77de163cf7ea9d71d5293a1bfa20d31fa6)
core: try to detect ipv6 addresses only when USE_IPV6 is used

- reported by Juha Heinanen
(cherry picked from commit b035aa9f2cc19d387b1b8f33a7888ffee27a4138)