Updates the view for the asset map

 - Adds rowspan to mach the number of rows in the variable
   names/variable units
 - Passes in another dict key "varcount" to view to assist in rendering.
Updates the metadata model to pair name and units

 - Wicken doesn't maintain the order between the names and units so this
   is a patch that deliberately fills in explicit metadata.
Adds more comments and descriptives
Fixes stack trace logging
Merge pull request #89 from ioos/units

Fixes the metadata relationship between the variable names and the units
Merge branch 'ra_pages' of https://github.com/ioos/catalog into ra_pages
Added regional/national provider distinctions
Added regional/national providers to index page dropdown
Fix regions filter instructions text

Fixes #66
Minor metadata cleanup for providers
Merge pull request #59 from ioos/ra_pages

RA Summary Pages
Set max-height on image files, fixes #26
Fixed extraneous zoom extent bug.  Fixes #94
Merge pull request #95 from benjwadams/fix_bbox_zoom_large_extent_bug

Fixed extraneous zoom extent bug.  Fixes #94
Added help tooltips to home page

Implements #69.  Added help text directly to "Services" and "Datasets"
 heading via tooltips.  Moved help text to separate include file in raw text,
 which both the main help and home page now include.

Also fixed capitalization error on
"NGDC Geoportal" and decapitalized "datasets" near end of help text.
Fixes bug in the status update
Merge pull request #98 from ioos/statusbug

Fixes bug in the status update
Merge pull request #97 from benjwadams/add_help_tooltips_to_home_page

Added help tooltips to home page
Merge pull request #93 from benjwadams/fix_region_filter_text

Fix regions filter instructions text
Dataset dropdown populated from active services

Fixes #65 by eliminating dataset asset types with inactive service endpoints
from the selection menu on the datasets page.