Changed eclipse project name
fix classpath problem
I use text indexing
Move type to new file
Deleted commented out old code etc
cache Tails
tidied up (legacy?) spaghetti logic in calc
Computes an estimated cardinality for the join group
deleted unreachable code
Use StaticOptimizer to estimate cardinality of unions
UnionNodes are reorederable
Deleted incorrect comment
Optimize unions along with static joins
Pulled out commonality
processing of unions requires more recursive analysis of vars
oops
Minor change to test that reflects improvements to optimizer