- Set window binds for channel items as sticky when re-creating window
binds as part of /layout save. This addresses the problem of previously
saved channel window items forgetting their windows upon reconnection,
which resulted in them being opened in new windows.
- Ensure that expando_cumode_space() doesn't free unallocated memory when no
prefix exists by conditionally allocating and marking to-be-freed the cumode
string inside of expando_cumode().
