Generate doxygen template for tutorial.
Exclude tutorial-specific files from main docs.
Add basic tutorial.
Fix location of layout file.
Move all tutorial files out of the main documentation.
Put tutorial images in the build directory.
Fix links between manual and tutorial.
Flesh out the tutorial introduction.
Show a simple example of using the IMP Python library.
Show the C++ equivalent to simple.py.
Flesh out the tutorial main page.
Fix spelling and grammar.