Adds notice for alpha release
Alpha banner can now be closed
Adds an about alpha modal

Reuses the download modal class to render some small about text. To be
removed soon!
Merge branch 'master' into banner

* master:
  Update docs about DB instances
  Updates bucket size for nginx name config
  Correct usage of tar to untar ruby and gdal sources
  Add staging and production databases
  add analytics and mouseflow tracking
  forgot to commit stats-img ages ago
Adds user voice
Temporarily remove extra feedback link in place of uservoice
Merge branch 'banner'

* banner:
  Temporarily remove extra feedback link in place of uservoice
  Adds an about alpha modal
  Alpha banner can now be closed
  Adds notice for alpha release
Merge branch 'master' of github.com:unepwcmc/ProtectedPlanet

* 'master' of github.com:unepwcmc/ProtectedPlanet:
  Changes country links to go to stats pages
  Correct type for shapefile downloads