Split admin.py into multiple files and improve search

Add ' + ' as a separator for multiple requirements
Closes #79

backend/spellbook/admin/__init__.py

@@ -0,0 +1,12 @@
+from .card_admin import CardAdmin
+from .template_admin import TemplateAdmin
+from .feature_admin import FeatureAdmin
+from .combo_admin import ComboAdmin
+from .variant_admin import VariantAdmin
+from .job_admin import JobAdmin
+from .log_admin import LogEntryAdmin
+
+from django.contrib import admin
+admin.site.site_header = 'Spellbook Admin Panel'
+admin.site.site_title = 'Spellbook Admin'
+admin.site.index_title = 'Spellbook Admin Index'

backend/spellbook/admin/card_admin.py

@@ -0,0 +1,15 @@
+from django.contrib import admin
+from ..models import Card
+
+
+@admin.register(Card)
+class CardAdmin(admin.ModelAdmin):
+    fieldsets = [
+        ('Spellbook', {'fields': ['name', 'features']}),
+        ('Scryfall', {'fields': ['oracle_id', 'identity', 'legal']}),
+    ]
+    # inlines = [FeatureInline]
+    list_filter = ['identity', 'legal']
+    search_fields = ['name', 'features__name']
+    autocomplete_fields = ['features']
+    list_display = ['name', 'identity', 'id']