Give more helpful error when POPIT_API_URL not set

closes #883
tweaked spacing between speeches
tweak heading size on homepage search for mid-sized screens
added list markup to results list
Wired up search box
wired up header search
Sort numerically as last resort.

Not sure why this was stringified, could cause reordering.
move location of list tags, now properly wrap results
Use database-based index name for search engine.
remove strong tags from speaker name
styling for speeches when appearing in search results
removed uneeded spacing from speech
readjusted image spacing, adjusted speech spacing
add layout code, heading markup
At top level section list, do not show descendants.
added search box markup, needs fixing to use the form object
removed old search code, replaced with new
removed extra chevron
corrected missing chevron
search in header now hides on search results page