color: don't split colors across lines (which confuses less -R) Currently, less -R doesn't support colors spanning multiple lines; only the first line will be colorized. Instead of allowing colors to span multiple lines, the color extension now applies colors to each line it receives, even when ui.write() is given multiple lines in one call.

adding file
% create a second head
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
created new head
% failing merge
0 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg update -C' to abandon
% resolve -l, should be empty