Problem:
- Configuring the height of one of the message targets to 1 is
recognized as 100% of 'lines'.
- Cmdline is expanded for message exceeding 'cmdheight' even if the
configured height is smaller than or equal to 'cmdheight'.
Solution:
- Recognize a height of 1 as absolute; a decimal number smaller than 1
is taken as a fraction of 'lines' (replace 1 with 0.999 for the old
behavior).
- Don't expand the cmdline if the configured height doesn't allow it.
70c3289290
