Revert "issue #7: make dialect to platform-independent databasePlatform."

This reverts commit 0c8e68d41cac448f3a3009a88a16445d2f8605a8.
Revert "issue #7: added databasePlatform and mark dialect to deprecated."

This reverts commit 975aaf69794466d88681a032d2365a783cb36712.