Broken spines code
Running and buggy spines
Fixed some spine bugs, and more remain
Fewer bugs. Rewriting is not catching everything we want
Found the missing case; added an unimplemented exception
Better, and still not handling reduction of subterms in matching
Basic spine support is working; next step: better hints about where to apply reduction to subterms
Realized there are 2 sorts of spine patterns: Pattern.Spine(-) and Pattern.Term(Syntax.Spine(-)).
Added a couple comments
Disabled some debugging output
Code cleanup in the top-level
Minor cleanup in the common code
Merge branch 'master' into spines

Conflicts:
	andromeda/andromeda.ml
Added some comments
Reorganize directory structure

Put Andromeda source into `src`.
Store `tt` source away.
Update .gitignore for version.ml
Changing some comments to ocamldoc style
Fixed Paris slides, close #47
Merge branch 'master' of https://github.com/andrejbauer/andromeda