let ghini.server handle the geographic client

[mfrasca]

the geographic client, we already have it as ghini.web, it can serve as an initial step towards ghini.guest. once it's served, we have to tie it to ghini.server.

todo

• add a map page next to results and pictures.
• make it show the map from osm (Leaflet).
• set initial view (initially hard coded)
• let institution data define initial view (add institution and collection information #83),
• add coordinates to Plant model (add geographic coordinates to plant model #79),
• propagate plant coordinates to Accession and Taxon,
• store search in hash,
• restore search from hash,
• show plants on the map, matching the Results,
• before any row is selected, centre map according to all Results,
• make sure we can associate a single Results row to multiple plant markers,
• show active plant(s) in different colour,
• when row in Results is clicked, Marker is highlighted too,
• if highlighted Marker falls outside map, map is re-centred,
• when plant in Map is clicked, row in Results is highlighted,
• if highlighted Results row falls outside view, view is re-centred,
• report same two-lines in popup,
• disable popup when moving out of map,

move to own issues:

• when selects area on map, search is updated,
• show icon in centre of marker (initially hard coded),
• add .icon and .layer_zoom fields to Plant model,