Merge the remainder of the new groupchats implementation

Commit history: https://github.com/jfreegman/toxcore/tree/ngc_jf
Spec: https://toktok.ltd/spec.html#dht-group-chats

Author: JFreegman

.cirrus.yml

@@ -92,6 +92,7 @@ bazel-tsan_task:
         -//c-toxcore/auto_tests:conference_av_test
         -//c-toxcore/auto_tests:conference_test
         -//c-toxcore/auto_tests:file_transfer_test
+        -//c-toxcore/auto_tests:group_tcp_test
         -//c-toxcore/auto_tests:onion_test
         -//c-toxcore/auto_tests:tcp_relay_test
         -//c-toxcore/auto_tests:tox_many_test

.gitignore

@@ -65,6 +65,8 @@ libtool
 .libs
 .dirstamp
 build/
+*.nvim*
+*.vim*
 
 #kdevelop
 .kdev/
@@ -88,3 +90,5 @@ cscope.files
 
 # rpm
 tox.spec
+
+.idea/