Add proposition-{tautology,equivalent}
Fix prop-simplify

  * Now recurses correctly
  * Also uses propositions-equivalent
Add de morgans laws in simplifications
Consider 'nil as unsatisfiable in minisat
Add finite-set-equivalent
Add pattern-lambda-else
Add gsymbol-equal
Add the new source files to the asd-file
Add more map functions for grammars
Generalize edge equivalence in fa comparisions
Merge commit '8d6cf46395b9844d7748964f1b7f71b205281c3a' into dev
Wrap MINISAT with PROP-SAT-P
Rename proposition-X to prop-X-p
Merge commit 'c29f95b' into dev
Fix and test FINITE-SET-EQUIVALENT

* Iterate and short-circuit
Merge commit '324e656cf1ea56831de0f14fdb750a5098d4b8da' into dev
Refactor GSYMBOL-EQUAL
Merge commit 'a3995472a6a93645a56027c976d004f5a6c1eb1d' into dev
Refactor GRAMMAR-MAP-*

* GRAMMAR-MAP-GROUPED takes result-type parameter
Merge commit '9901494e8fc8b4c40d845d2ed4a98583aafe69d1' into dev