Synchronize get_all_snapshots() with current version of API
Merge remote-tracking branch 'C2Devel/pull-request-snapshots' into pull-request-snapshots
Tests for #1554, remove unneeded compatibility layer
Merge pull request #1813 from mbarrien/pull-request-snapshots

Add support for filtering by multiple account IDs to EC2 get_all_snapshots. Fixes #1813, #1554.