- Add support for virtual (aka. hardoded table in ha_ndbinfo).
- Extracted NdbInfoScanoperation to become an abstract interface
  to allow different scan implementations. The NdbInfo classes
  are internal so this is fine. Rename existing scan implementation
  to NdbInfoScanNodes which reads from the tables in the data nodes
  and then added new NdbInfoScanVirtual which reads from the virtual
  table. The factory function createScanOperation() decides which one
  to create based on the "virt" member in Table.
- Create virtual table in Ndbinfo::init() and destroy them in
  destructor. This is important since the Table class  has
  pointer(s) to these tables. Alternatively the pointer could have been
  avoided at the cost of one hash lookup in createScanOperation() to
  determine if the table is virtual or not.
- Implement ndb$blocks, ndb$dict_obj_types, ndb$config_params,
  ndb$dbtc_apiconnect_state and ndb$dblqh_tcconnect_state
- Added SQL to create the above tables.
- Added SQL to create backward compatibility views for the three old
  table names -  blocks, config_params and dict_obj_types
- Updated ndbinfo_sql to generate code for the new virtual tables,
  drop the "old" tables and create the new views.
- After this patch all tables in ndbinfo should have engine = NDBINFO.