Encounters with observations forms with non grouped coded obs controls not syncing to OpenERP

[Biruk-Abebe-Y]

Encounters with lab and medication orders that also contiain observations captured using forms with non-grouped coded obs control created using implementers interface cause a parse error at bahmni erp connect.

To duplicate this issue:

1. create a form using implementers interface
2. add an obs control whose data type is coded
3. save the form
4. capture an observation using the newly created form and put lab or medication orders
5. The orders will not be synced to OpenERP

Attached is partial (relevant) output a got from bahmni-erp-connect log
openerp-feed-service.log

I have created a PR for a possible fix for this issue #22