fixed get_all_adjustment_types for ec2/autoscale

Signed-off-by: Pascal Hakim <pasc@redellipse.net>
added adjustment types unit test

Signed-off-by: Pascal Hakim <pasc@redellipse.net>
Actually check results in TestGetAdjustmentTypes unit test
Merge remote-tracking branch 'pasc/autoscale_get_all_adjustment_types' into develop
Fixes #2058, #1538.