* Use `literal::UnsignedInteger` instead of `atoi`.
* Combine common code for `_fromDir`, `_fromFile` to `_fromText`.
* Pass `dmFilePathArgs_t` as a const reference instead of pointer,
don't write result codes to this struct.
* This patch adds file2Oid function. This function is needed
to map ColumnStore file name to an oid, partition and segment.
* Tests added to check that this function works correctly.
* This patch is related to MCOL-4566, so it adds a new file with GTests.
Note: The description for the functions follows the description style
in the current file.