m_spanningtree Send, parse and translate IJOINs with membership ids
m_spanningtree Add CmdBuilder specialization for FJOIN
m_spanningtree Use the FJOIN builder when a channel is created
m_spanningtree Add CmdBuilder::push_raw_int()
m_spanningtree Send and parse FJOINs with membership ids
m_spanningtree Translate FJOINs with membership ids for 1202 protocol servers

Strip all membership ids from outgoing FJOINs
Send the membership id when kicking a remote user and drop KICKs with mismatching membership ids