Fix bug in sender rtt prometheus stats. They should be displayed in units of second and not millisecond
Closes #178

Fix new NPD test: we cannot repeat port numbers or the tests interfere with each other as they are executed in parallel

Null packet deletion fix: do not assume we have 7 mpegts segments per packet during null restoration.

Enhance test application: 1- Use random packet sizes. 2- Emulate mpegts and check sync bytes. 3- Add tests for null packet deletion mode.

Fix random data corruption on the rist receiver upon arrival of keepalive packets. The code was incorrectly using memcpy to populate an unpacked structure.

We were using payload_type < 200 and now we use a range outside 200 to 205 for the classification.
When the marker bit of the rtp header is turned on, the payload type of the rtp packet could match the range we were looking for, thus incorrectly classifying rtp data as rtcp data. For example, STMPE-2110 uses rtp payload types 96 through 127 (224 to 255 with the marker bit on).
With this fix, librist will also classify rtp packets with a payload type of 72-77 as rtcp. Since that range is reserved for “RTCP conflict avoidance” on the RFC4855 standard, we can leverage that to add a feature to the library (keep reading).
Lastly, let it be documented that the library WILL only classify rtp packets as rtcp if they live in the range 200-205 or 72-77. Everything else is considered rtp data.
If anyone wants to use custom rtcp packets not defined in the RIST specification and they want their implementation to work with librist, they must use the 72-76 range or they will be treated as rtp data and run the risk of corrupting their data stream.

More Readme updates

See merge request rist/librist!256

# Conflicts:
#   README.md

Readme updates

See merge request !255

Fix socket deadlock under windows

Closes #185

See merge request rist/librist!254

Fix LOGGING_SETTINGS_INITIALIZER macro to be compatible with versions of C++ below C++20

Closes #183

See merge request !253

calloc

See merge request !249

# Conflicts:
#   include/meson.build
#   meson.build

Issue_181 and Issue_179

Closes #179 and #181

See merge request rist/librist!252

Few corrections of the librist

See merge request rist/librist!250

Update peer config to use rist_timing_mode enum for timing_mode field

See merge request rist/librist!248

Fix alignment issues in oob_build_api_payload

See merge request rist/librist!247

Update meson usage to avoid using future-deprecated meson.source_root

See merge request rist/librist!246

fix logging typos in rist_sender_npd_{enable,disable}

See merge request rist/librist!245

Add `rist_sender_npd_get` for querying null-packet-deletion status

See merge request rist/librist!244

ristreceiver closes sometimes if tun://@ is used in output url.

Closes #176

See merge request rist/librist!243

Fix deadlock on fifo overflow

See merge request rist/librist!242