Removed references to is_sortable from the tests.
Removed references to is_sortable from the tests.

scholarslab/SolrSearch,CATCH-FACT/SolrSearch-VB,micongrin/plugin_SolrSearch-WMI,CATCH-FACT/SolrSearch-VB,anuragji/SolrSearch,anuragji/SolrSearch,micongrin/plugin_SolrSearch-WMI,CATCH-FACT/SolrSearch-VB,scholarslab/SolrSearch,CATCH-FACT/SolrSearch-VB,anuragji/SolrSearch,anuragji/SolrSearch,micongrin/plugin_SolrSearch-WMI,scholarslab/SolrSearch,scholarslab/SolrSearch