Integration tests to verify cli tool commands used in extension works with new version released

[dgolovin]

To avoid compatibility issues between odo releases there should be integration tests to run:

• with latest nightly oc/odo build to detect problems early
• with latest official oc/odo release to verify compatibility before extension release

[datho7561]

I'd be interested in working on this for next sprint. We have npm urn test-integration, which runs a bunch of odo and oc commands, but currently it's broken. I'd like to fix it. It might also involve cleaning up some broken methods in src/odo.ts