- Some of the Transformation classes would initialize their Action's
action_kind using the default (using Transformation constructor
without an action_kind parameter).
- Others, however, would use that constructor and initialize action_kind
manually in their constructor, but setting the default value
(RunTimeBeforeMatchAttemptKind = 1), which was redundant.
- Removed unused Transformation constructor to specify action_kind.
- Converted Action::Kind into an 'enum class' to require using the enum
constants (instead of integer values, which are difficult to track in
the codebase and change)