Fix and enable some of the tests; some remain disabled.
The tests innodb_gis.rtree_old and innodb_gis.row_format
duplicated some versions of the test main.gis-rtree.
Instead of duplicating, source that test, in a new test
innodb_gis.innodb_gis_rtree.
Introduce innodb_row_format.combinations. Due to this,
ROW_FORMAT=COMPRESSED will not be covered in some tests
where it is covered in MySQL 5.7.