Use -traditional-cpp as preprocessor argument to prevent breaking URLs.

Modern C preprocessors omit comments in their output. Unfortunately, C-style
comments may start with `//'. Hence, the rest of the line after `http://' is
interpreted as comment and omitted, resulting in a broken LaTeX file.
The -traditional-cpp flag prevents this from happening.
Add default rules to generate all relevant .pdf / .hs files.
Add README for slides.
Merge pull request #1 from bertm/patch-slides

Patches for compiling slides