0026469: Methods Seek(), ChangeSeek() are missing in class NCollection_IndexedDataMap

0026469: Methods Seek(), ChangeSeek() are missing in class NCollection_IndexedDataMap

I. New features:
1.1. class NCollection_IndexedDataMap
 - method:
 const TheItemType* Seek(const TheKeyType& theKey1) const
 has been added.
 The method Seek returns pointer to Item by Key.
 Returns NULL if Key was not found.

 - method:
 TheItemType* ChangeSeek (const TheKeyType& theKey1)
 has been added.
 The method ChangeSeek returns modifiable pointer to Item by Key.
 Returns NULL if Key was not found.

II. Changes:
 No changes.

III. Modified entities:
 packages:
 NCollection