saved unification failing equality in SymbolicConstraint for debugging
removed #Id leftover
add DependsOn annotation to denote compiler passes that must run after
another compiler pass
on second thought, this is better
fix compile error
add javadocs
handle builtin and token sorts more generally in the java backend
renamed README to README.md
updated README
updated README
updated README in lesson 2
updated readme in lesson 2
updated README in lesson 3
updated readme in lesson 4
updated readme file of lesson 5
updated readme file of lesson 6
Merge pull request #247 from dwightguth/master

add DependsOn annotation to denote compiler passes that must run after another compiler pass
indexing: progress on tuning indexing algorithm and better profiling
indexing: minor cleanup
indexing: many minor changes