Improve code formatting according to CMP.

Add one pair of braces for clarity, move some other braces and
else statements around. There's more to that, but these were
minimal changes to improve readability for solving STR #3043.
There are no real code changes involved though.


git-svn-id: http://seriss.com/public/fltk/fltk/branches/branch-1.3@10474 ea41ed52-d2ee-0310-a9c1-e6b18d33e121