[ fix-agda-withespace ] Allowed more versions of the directory library

GHC 7.0.4/7.4.2 use directory 1.1.0.0/1.1.0.2 so fix-agda-whitespace
should use the same versions on Travis.
Merge branch 'maint-2.4.2'
[ LaTeX-backend ] Tweak agda.sty: saner default font (XITS), texttt
rather than mathtt for comments and strings, and change the font for
arguments...
[ LaTeX-backend ] Clean up after the fix of issue 1062, and properly end
the escaped commends for ~, ^ and \\ with {}.