Update the sleuthkit to 4.1.3:

• Use libtool (instead of jumping from .11 to .12, we go back to .10)
• Include a patch which allows python bindings to work correctly (obtained from Joachim Metz)

Update pytsk to 2014-02-09:

• Remove DOCS/EXAMPLES conditionals
• Don't override DOCSDIR and EXAMPLESDIR, mva's patch will do it soon