cleanup

- unify multi-line expression alignment style.
- unify multi-line function call alignment style.
- simplify client moving on monitor count decrease.
- clarify comment for focusin().
- remove old confusing comment about input focus fix in focusmon(). The
  explanation is already in the old commit message, so no need to keep it in the
  code.
- remove old comment describing even older state of the code in focus().
- unify comment style.
- break up some long lines.
- fix some typos and grammar.

LICENSE

@@ -16,7 +16,7 @@ MIT/X Consortium License
 © 2011 Christoph Lohmann <20h@r-36.net>
 © 2015-2016 Quentin Rameau <quinq@fifth.space>
 © 2015-2016 Eric Pruitt <eric.pruitt@gmail.com>
-© 2016 Markus Teich <markus.teich@stusta.mhn.de>
+© 2016-2017 Markus Teich <markus.teich@stusta.mhn.de>
 
 Permission is hereby granted, free of charge, to any person obtaining a
 copy of this software and associated documentation files (the "Software"),