Added oppositeIndex to CanonicalExpression.
Corrected bug in IntVal.opposite.
Added representation abbreviation in display of Expr tensor ascii.
Corrected bug in BellExpressionProduct Rewritable implementation.
Implemented reading of canonical expressions with upper and lower reconstitued bounds.
Corrected bug in DiskBinBranch.lastInt
Removed unneeded commented out code.
Implemented retrieval of canonical expressions, and explicit instantiation of those.
Added CompHash, CompHash implementation in memory, CompCanonical implementation from Hash and Readable.