Remove / fix result code logic and improve image saving process

[sanjiva]

Need to:

• make sure image is for a release for which data has been sent
• while unlikely, need to support the ability to re-issue a result for a particular area

[sanjiva]

Code can be 2 digit district code + A letter PD code within the district

[sanjiva]

Result code added in cbb5009

[MaryamZi]

Few clarifications:

Need to:

• make sure image is for a release for which data has been sent

By this do we mean ensuring an image is saved only after the corresponding result has been delivered to the subscribers?

• while unlikely, need to support the ability to re-issue a result for a particular area

The impact of this would be the following?

• distributor - updates to the database and re-sending the results to the subscribers
• subscriber - this will just overwrite the existing file