Mammo sorted by AGD creates duplicates in export

[Ed McDonagh]

Warning in interface that ordering by AGD will create duplicates, which it doesn't. However it does in the exports.

View has .distinct() which export doesn't.

[Ed McDonagh]

Checks for AGD ordering in NHSBSP export and replaces it with date to avoid duplicates. Need to replicate for other two mammo exports. Refs #641

→ <<cset 8c0fcf27884d>>

[Ed McDonagh]

Replicated filter fix for csv and xlsx exports. Refs #641

→ <<cset 9e8c17002a10>>

[Ed McDonagh]

Removed duplicate if AGD warning as it is no longer valid. Refs #641

→ <<cset 637dff53bf97>>

[Ed McDonagh]

Reworked the dictionary update to check if dict and has value first. Test was passing empty string - now changed to pass empty dict. Refs #641

→ <<cset 82379751b479>>

[Ed McDonagh]

Applied the same change to nhsbsp export. Refs #641

→ <<cset 18ccf7c09d05>>

[Ed McDonagh]

Starting to do the tests for refs #640, #641

→ <<cset 3766f887f6ed>>

[Ed McDonagh]

Tests for refs #640, #641

→ <<cset 11aeba9c33a7>>

[Ed McDonagh]

Updating changes for refs #640, #641

→ <<cset a691fb7c4cdb>>

[Ed McDonagh]

Merged in issue640nhsbspexportbroken (pull request #205)

Fixes #640, #641

→ <<cset def13214ec4f>>