warning:
* may be buggy
This commit adds support for sideways splits into Irssi. To that regard,
there are a number of new commands available
the "R" commands:
/window new rsplit - make a new sideways split
/window rshow - show an existing window to the right
/window rgrow/rshrink/rsize/rbalance
- manipulate the size of your sideways split windows
the "D" commands:
/window dup/ddown/dleft/dright
- navigate the windows directionally, as an alternative to
/window up/down that you can bind to some key
/window move dleft/dright - the same for moving
Enjoy!