databases/cego: update 2.48.48 -> 2.49.0, cegobridge 1.6.5 -> 1.7.0

- In CegoCaseCond, added getPlanList method to retrieve execution plan
  for nested selects. The planlist then is catched in CegoFactor::getPlanList
- Consolidation done for data types decimal and fixed.
  This version just supports the decimal datatype which originally was
  the fixed datatype. The original decimal datatype was useless.
  IMPORTANT: To migrate to version 2.49, you have to xml export
  the databases and rename the datatype strings "fixed" and "FIXED"
  to "decimal" and "DECIMAL"
- cegobridge needs to be rebuild