Adds support for rewriting with backreferences: A -> || C _ D (no RHS) where A is transducer; bugfix in L^>n. Memory cleanup.
Adds support for rewriting with backreferences: A -> || C _ D (no RHS) where A is transducer; bugfix in L^>n. Memory cleanup.

alishir/foma,alishir/foma,alishir/foma,alishir/foma