Bugfix.  https://github.com/52North/sos-js/issues/13.

The offering search autocomplete list appeared under the map, because its default z-index was 1.  We now add a CSS class to its parent (offering menu panel) with a z-index higher than the map default.
Bugfix.  https://github.com/52North/sos-js/issues/17.

The temporal coverage for the whole SOS instance is often present in the service's capabilities document, and is used to populate the right-hand Metadata info box in the SOS.App.  This mod. improves the robustness of checking that this temporal coverage exists in the capabilities document, before trying to use it.