* xmlschemas.c: Added IDC validation of anySimpleType attribute
  values; anyway the IDC key comparison is restricted to
  anySimpleType <--> string based types. For other types we
  would possibly need the canonical lexical representation of
  them; this sounds not performant, since we would need to
  build such a representation each time we want to compare against
  anySimpleType. TODO: think about buffering the canonical values
  somewhere. Fixed error reports for default attributes to work
  without a node being specified. This all and the enabling of IDC
  validation fixes bug #165346 (reported by Benoit Gr?goire - could
  not read his last name correctly from bugzilla).