RLS: 0.7 release notes
RLS: 0.7 release notes

Author: Wes McKinney <wesm@apache.org>

Closes #802 from wesm/docs-0.7 and squashes the following commits:

26ec20e [Wes McKinney] Change release date to 3/16
e26fb5f [Wes McKinney] Draft 0.7.0 release notes

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