C API cursor handle method names

In the Berkeley DB 4.6 release, the C API DBC handle methods have been renamed for consistency with the C++ and Java APIs. The change is the removal of the leading "c_" from the names, as follows:

DBC->c_close
Renamed DBC->close

DBC->c_count
Renamed DBC->count

DBC->c_del
Renamed DBC->del

DBC->c_dup
Renamed DBC->dup

DBC->c_get
Renamed DBC->get

DBC->c_pget
Renamed DBC->pget

DBC->c_put
Renamed DBC->put

The old DBC method names are deprecated but will continue for work for some number of future releases.