CI/COV: Add pull request comments from codecov
CI/COV: Add pull request comments from codecov

Author: Phillip Cloud <cpcloud@gmail.com>

Closes #1515 from cpcloud/codecov-comments and squashes the following commits:

3bea14f [Phillip Cloud] CI/COV: Add pull request comments from codecov

cloudera/ibis,cpcloud/ibis,deepfield/ibis,deepfield/ibis,cpcloud/ibis,deepfield/ibis,cpcloud/ibis,cloudera/ibis,ibis-project/ibis,ibis-project/ibis,ibis-project/ibis,deepfield/ibis,cpcloud/ibis,ibis-project/ibis,cloudera/ibis