cmode_b: Correction to the maxbans conditional
It was possible to set one more ban beyond the configured limit.
Merge pull request #397 from Robby-/insp20+cmode_b-limit

[2.0] cmode_b: Correction to the maxbans conditional
m_maphide Ignore unregistered users

Fixes #400 reported by @SaberUK
m_spanningtree Fix rare desync when a KILL crosses a message that has the killed user's prefix and modifies global state
Fix warning: "const type qualifier on return type has no effect".
Merge pull request #403 from SaberUK/insp20+wextra-fixes

Fix warning: "const type qualifier on return type has no effect".