Fix unescaped characters in facet URL
Fix unescaped characters in facet URL

When a facet includes special characters, it is necessary to escape them
properly.

Fixes #115.

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