srt: Integrate server and client element into one

We have srt{client,server}{src,sink} elements in accordance to the
norm of the connection oriented protocols. However, SRT connection
mode can be changed by uri parameters so it requires an integrated
element to handle the parameters.

fix: #740
8 jobs for issue/740 in 121 minutes and 10 seconds (queued for 59 minutes and 29 seconds)
Status Job ID Name Coverage
  Preparation
passed #77002
gst indent

00:00:32

passed #77001
manifest

00:00:23

 
  Build
passed #77003
build fedora x86_64

00:04:13

 
  Test
passed #77004
check fedora

00:16:53

 
  Full Builds
passed #77005
build android arm64 api28

00:03:14

passed #77007
build cerbero cross win32

00:42:58

passed #77008
build cerbero cross win64

00:43:25

passed #77006
build cerbero fedora x86_64

00:13:47