Support for Linux and cross-platform git settings

[jaccokrijnen]

Here are some changes to get everything running smoothly on linux (well, on my Ubuntu installation :) ).

• Line endings: I've added a .gitattributes file, to let git properly manage the newline symbols of different operating systems (CRLF on Windows and LF on Linux/Mac). Whenever git checks out the files, it will choose the newline symbols to the platform-appropriate ones (but internally it commits files in a consistent way, using LF).
• I've renormalized all files because line-endings were not consistent (some were CRLF, others LF)
• Filesystem paths on linux are case-sensitive, so I've modified a few \includes (changed "Backmatter" -> "BackMatter")
• I've added a simple Makefile for people that like to use make. It just runs pdflatex and biber as instructed in the README