Renamed MshEnums.{h,cpp} to MeshEnums.{h,cpp}.
struct MshElemType -> enum class MeshElemType.
struct CellType -> enum class CellType.
struct MshQualityType -> enum class MeshQualityType.
struct UseIntensityAs -> enum class UseIntensityAs.
enum MeshDensityAlgorithm -> enum class MeshDensityAlgorithm.
enum OGSType -> enum class OGSType.
enum LUTType -> enum class LUTType.
struct UseIntensityAs -> enum class UseIntensityAs.
enum VtkTargetObject -> enum class VtkTargetObject.