Ibdint object can now write its entries.
Fixed chg model so user can upload BO data without lc number.

This is to arrest the situation where user will input lc number
into BO excel, tehn close the swift message and then put enter
another lc number only to later go to the admin and repeat the
same process for swift texts. This is wicked.
Begin refactoring disc.py to use django orm
Almost done refcatoring ibdint.py
Finished refactoring disc.py to use django orm
Model ibdint self validation for ccy and lc number.

Ibdint now validates itself to ensure that the account number's
ccy is same as transaction ccy. Also, it validates that LC number
is valid.
Merge branch 'develop' of https://github.com/samba6/recons into develop