HUE-2138 [search] Slider widget UX

Reduced font size on the input
Fixed min/max problem
HUE-2141 [search] Fail gracefully when a collection does not exist

Added PopupException
HUE-2130 [search] Prettyfy empty result

For both HTML and Grid layout
HUE-2135 [search] Support non Solr cloud mode

Merge duplicated SolrApi
Search and index listing is compatible with non Solr Cloud mode
Cannot create a core in indexer in non Solr Cloud mode
[search] Adding user agent bar chart to the Apache log example