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.

config.def.h

@@ -15,7 +15,7 @@ static const char col_cyan[]        = "#005577";
 static const char *colors[][3]      = {
 	/*               fg         bg         border   */
 	[SchemeNorm] = { col_gray3, col_gray1, col_gray2 },
-	[SchemeSel] =  { col_gray4, col_cyan,  col_cyan  },
+	[SchemeSel]  = { col_gray4, col_cyan,  col_cyan  },
 };
 
 /* tagging */