- The String type now generates VARCHAR2 on Oracle

  - The String type now generates VARCHAR2 on Oracle
    which is recommended as the default VARCHAR.
    Added an explicit VARCHAR2 and NVARCHAR2 to the Oracle
    dialect as well.   Using NVARCHAR still generates
    "NVARCHAR2" - there is no "NVARCHAR" on Oracle -
    this remains a slight breakage of the "uppercase types
    always give exactly that" policy.  VARCHAR still
    generates "VARCHAR", keeping with the policy.   If
    Oracle were to ever define "VARCHAR" as something
    different as they claim (IMHO this will never happen),
    the type would be available.  [ticket:2252]