fixes OpenTreeMap/otm2-addons#296

-Made the instance name column a fixed width with ellipses rather than
a horizontal scroll bar.
Merge pull request #1786 from ctaylo37/Fixes-#296

fixes OpenTreeMap/otm2-addons#296
There is no need to have 2 <meta charset="utf-8"> tags
Merge pull request #1785 from RickMohr/unstructured-species-period-fields

Convert species "choice" fields to unstructured text
Merge pull request #1787 from maurizi/remove-extra-meta

There is no need to have 2 <meta charset="utf-8"> tags
Fix scrollbar in Importer "status" tables

Now it scrolls just the very-wide table, and not the pagination buttons below it.
Auto-refresh pending imports

* Factor out `import-tables.html`,  including hidden `importsFinished` field indicating if all imports have finished
* In `importsList.js`, test that field whenver content is loaded, and refresh all tables if imports haven't finished
* New endpoint `refresh_imports_endpoint`
* Refresh every 5 seconds
* Start refreshing when "Bulk Imports" tab is shown, and stop when tab is hidden
* Clean up `import_table.html` and show spinner until import completes