Fix breadcrumbs on admin
Don't assume faceting is enabled in Solr JSON response. Fixes #389.
Use POST for dispatching Solr queries. Fixes #377.

This prevents errors when using a large number of exclude arguments.
Restore optionality in search param page and count. Fixes #379.

These params are actually optional on the form and giving them
defaults prevents overriding them from the call site, which is
useful (and indeed used in some places, such as the home page.)
Tweaks to admin date rendering (fixes #338)
Correct rendering of markdown in list items on admin (fixes #385)
Rename 'provenance' field to 'processInfo'. Fixes #386.
Generalized SparQL form so it can be used for Cypher as well. Added streaming cypher method.
Merge branch 'master' into virtual_collection_rework
Merge branch 'virtual_collection_rework' into merge_guides2