OCL subscription module - Improve error message while importing concepts from Dictionary Manager using subscription module

While importing concepts from Dictionary Manager to OpenMRS using subscription module user often face different types of errors, which needs to to addressed, and the different errors are:

1. Error found: Shows error found but import all the concepts
2. Some Java error: Shows some error like HTTP/1.1 208 Already Reported caused by: java.io.IOException: HTTP/1.1 208 Already Reported which is not clear

 To see these for yourself, try clicking around the subscription history in the dev3.openmrs.org environment. 

Subscription url: https://api.openconceptlab.org/orgs/openmrs/collections/demopackagehiv/9

Token: 001aaefa19fdc2915da5c270f6065da1a00d1190