enhancing makeApiCall to take endpoint uri only

[ScorpionFiko]

makeApiCall has been enhanced so that it makes a call to Quickbooks when:

• user provides the full prod or sandbox URL (backward compatibility)
• user provides the relative endpoint URL (/v3/company/...). It automatically pre-pends the sandbox or production URLs based on the environment property. This makes a seamless transition between sandbox and production.

Test cases for the change have been added

Test cases for setAuthorizeURLs have been added to increase the test coverage to the required level

BEFORE
=============================== Coverage summary ===============================
Statements : 94.68% ( 731/772 )
Branches : 82.82% ( 164/198 )
Functions : 92.11% ( 187/203 )
Lines : 95.46% ( 716/750 )

AFTER
=============================== Coverage summary ===============================
Statements : 95.8% ( 799/834 )
Branches : 85.57% ( 178/208 )
Functions : 93.27% ( 208/223 )
Lines : 96.54% ( 782/810 )

[rajeshgupta723]

Thanks, these changes are approved to go.