type for tactic node

[lyhlbyl]

• get rid of the use K in parser, need a better solution

• Adding tactic types for tactic nodes to distinguish env_tac and tac, instead of using ENV_. By default, a node is a tactic node.
  tactics:

  • tac_name
  • tac_name (args, ... )
  • tac (X) : tac

  env tactics:

  • tac_name (args, ... ) : env