Add coordinates autocomplete widget & data (#32)

Just tweaks based on what Carl had already written in dce53630 and b97d421a

apps/map/admin.py

@@ -1,14 +1,30 @@
 from django.contrib import admin
+from django import forms
+from dal import autocomplete
 from leaflet.admin import LeafletGeoAdmin
 
-from .models import CaseStudy, CaseStudyDraft
+from .models import CaseStudy, CaseStudyDraft, SpatialRefSys
+
 
 class CaseStudyDraftAdmin(admin.ModelAdmin):
     model = CaseStudyDraft
 
+
+class CaseStudyAdminForm(forms.ModelForm):
+    class Meta:
+        model = CaseStudy
+        widgets = {
+            'coordinate_reference_system': autocomplete.ModelSelect2(
+                url='srs-autocomplete'
+            )
+        }
+        fields = '__all__'
+
+
 class CaseStudyAdmin(LeafletGeoAdmin):
     list_display = ('id', 'date_created', 'entry_name', 'approved')
     actions = ['approve', 'unapprove']
+    form = CaseStudyAdminForm
 
     def approve(self, request, queryset):
         updated = queryset.update(approved=True)
@@ -33,5 +49,5 @@ class CaseStudyAdmin(LeafletGeoAdmin):
     unapprove.short_description = "Un-approve selected case studies"
 
 admin.site.register(CaseStudy, CaseStudyAdmin)
-
+admin.site.register(SpatialRefSys)
 admin.site.register(CaseStudyDraft, CaseStudyDraftAdmin)