### Description Current `parser_fline.c` is not supports HTTP/2 protocol and generates errors like below This is happens because [`HTTP_VERSION`](https://github.com/kamailio/kamailio/blob/cfc89db53c087382c29d809dc0bc56f735...) macro designed to work only with [`HTTP/1.x`](https://github.com/kamailio/kamailio/blob/cfc89db53c087382c29d809dc0bc56f735...) protocol.

### Expected behavior Response from `HTTP/2` enabled server is parsed without error.

#### Actual observed behavior ``` 246(251) ERROR: <core> [core/parser/parse_fline.c:257]: parse_first_line(): parse_first_line: bad message (offset: 11) 246(251) ERROR: <core> [core/parser/msg_parser.c:675]: parse_msg(): ERROR: parse_msg: message=<HTTP/2 200 date: Tue, 08 Jan 2019 15:12:16 GMT content-type: text/html; charset=UTF-8 server: Apache/2.4.37 (Amazon) OpenSSL/1.0.2k-fips PHP/7.2.11 cache-control: no-transform,public,max-age=300,s-maxage=900, no-cache, private set-cookie: laravel_session=eyJpdiI6ImZGbU96ajZPV2lkVGZLeHJFNlwvNEJ3PT0iLCJ2YWx1ZSI6IjZmdWdLT0JNNUNFU1ppRWtOTVlmTVphaG4yM25ZcHFWUmUrdlhpMXlYZ2dKK3NYT3JmeG82MkNrSW9VZHdhRkgiLCJtYWMiOiI5MmI1ZWY1YWY1ZDQ3N2Q5ZGMyNzY2OGM2M2ZmNGNlNmY1MGRmYzcyMDhkZTFjM2ZkOTFjMWJlNTRkZmM3MmJkIn0%3D; expires=Tue, 08-Jan-2019 18:12:16 GMT; Max-Age=10800; path=/; httponly access-control-allow-headers: origin, x-requested-with, content-type access-control-allow-methods: PUT, GET, POST, DELETE, OPTIONS

{"type":"registration_update","error_code":200,"text_description":"registration_update request succedded","call_id":"FrrQl6Dp~l"}> ```

#### Debugging Data None

#### Log Messages None

#### SIP Traffic None

### Possible Solutions Not know by me

### Additional Information

* **Kamailio Version** - output of `kamailio -v`

``` / # kamailio -v version: kamailio 5.1.6 (x86_64/linux) flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144 MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: unknown compiled on 03:24:34 Nov 23 2018 with gcc 8.2.0 ```

* **Operating System**: ``` / # cat /etc/os-release NAME="Alpine Linux" ID=alpine VERSION_ID=3.8.0 PRETTY_NAME="Alpine Linux v3.8" HOME_URL="http://alpinelinux.org" BUG_REPORT_URL="http://bugs.alpinelinux.org" ```