kleisli: Refactor as independent feature
istar: Initial stub for backward analysis

 * Add stub for REJ14 operator
 * Add some operator util functions into the operator class
operator: Simplify (1)

 * Move read input properties functions into Operator
 * Automatically invoke them, no need to invoke manually in execute()
Merge branch 'master' of https://github.com/adisandro/MMINT
tosem: Add Graph_MAVO projects
tosem: Remove LabeledGraph projects
tosem: Rename LabeledGraph directory into Graph
tosem: Reorganize feature names
tosem: Enable operators with no input parameters
tosem: Add Graph_MAVO operators project
tosem: Done GenerateRandomGraph operator
tosem: Make GenerateRandomGraph prettier
bug: Better handle errors when creating heavy operator types
tosem: Fix EcoreMAVOToSMTLIB when Node and Edge are metamodel classes
tosem: Add stub for may-only smtlib encoding
tosem: Add may-only encoding generation option to EcoreMAVOToSMTLIB
tosem: Add stub for updated TOSEM12 operator
tosem: Add mavo + classical property checks to TOSEM12

 * Reuse code from mavo check constraint (isolate in own function)
 * Refactor some function names
 * Remove duplicate MAVOTruthValue enum
tosem: Unify init() invocation
tosem: Add concretizations generation to TOSEM12