Fixed bug #76908 PDO_OCI getColumnMeta() not implemented

* Letargie-feature-getcolumnmeta:
  Removing last unused
  Last few changes : 	. force the nls_date_format 	. add the scale to the return of the function 	. add tests on some function return 	. removing unused variables
  cs
  Changes : . Add the distinction between NUMBER and FLOAT types . Changing BFLOAT text to be BINARY_FLOAT . Changing BDOUBLE text to be BINARY_DOUBLE . Add the data types names for NCHAR, NVARCHAR and NCLOB . Few changes in the tests
  fixing comments
  Update oci_statement.c
  Add the PDOStatement::getColumnMeta() function to the pdo_oci driver