* fix Nexus asset query issue.

was not constructing continuationToken URL correctly.

* ignore temp artifact files.

* unit test for download-artifact

* update cached download-artifact.js

* ignore download-artifact test from zap unit tests.

* download-artifact: add unit test / delegate to Github if specified branch is not cached on Nexus

intended for internal jenkins PRs that specifies a non-cached ZAP branch
on Nexus

* typescript
* do not check for github token when downloading from Nexus

* instrument codebase via babel-plugin-istanbul for Cypress
* direct jest report to jest-coverage / cypress report to cypress-coverage 
* combine/display code coverage report from all tests via "npm run report"

BUG:  ZAPP-774

0. Enshrine privilege as an alias for role.
1. Update some script that was path sensitive.
2. Ignore generated package file.