Implementation of SQLSetDescRec & SQLGetDescRec functions

[Hunaid2000]

Resolves #21.

• Completed implementation of SQLSetDescRec function.
• Fixed SQL_DESC_PRECISION field in IPDSetField & IPDGetField functions.
• Added support for following fields for bookmark column in ARDSetField .
  • SQL_DESC_TYPE
  • SQL_DESC_DATETIME_INTERVAL_CODE
  • SQL_DESC_OCTET_LENGTH
  • SQL_DESC_PRECISION
  • SQL_DESC_SCALE

Note: I am now working on SQLGetDescRec implementation.

[Hunaid2000]

Implementation for both functions is completed.

Other changes:

• Handled SQL_NO_DATA case in GetField functions
• Handled 01004 SQLSTATE in GetField functions
• Added support for SQL_DESC_NAME & SQL_DESC_NULLABLE in IPDGetField function

[Hunaid2000]

@davecramer any update on this?

[davecramer]

@Hunaid2000 Ideally we would add tests for these new functions ? Any chance you can add them ?

[Hunaid2000]

I will try to add them.

[Hunaid2000]

@davecramer I have added regression test.