- In CegoSelect::evalSelection, optimization provided in a way,
  that schema is not evaluated explizit anymore. Rather the previous
  analysed schema ( prepare method, _evalSchema ) is used. Since for
  dynamic field length, the resulting schema must be estiamated, this
  approach is ok.
- Fix added in CegoFunction::getReturnTypeLen, evalFieldValue for
  expression values could fail, since FLA ist still not set up. For
  this case, now the cont value RETVAL_LEN is returned as an estimation.

Submitted by:	Bjoern Lemke <lemke@lemke-it.com>