Change unique canonical keys to generic object key

app/views/api/v1/grid_characters/base.json.rabl

@@ -3,6 +3,6 @@ attributes :id,
     :position,
     :uncap_level
 
-node :character do |c|
+node :object do |c|
     partial("characters/base", :object => c.character)
 end

app/views/api/v1/grid_summons/base.json.rabl

@@ -5,6 +5,6 @@ attributes :id,
     :position,
     :uncap_level
 
-node :summon do |s|
+node :object do |s|
     partial('summons/base', :object => s.summon)
 end

app/views/api/v1/grid_weapons/base.json.rabl

@@ -4,6 +4,6 @@ attributes :id,
     :position,
     :uncap_level
 
-node :weapon do |w|
+node :object do |w|
     partial("weapons/base", :object => w.weapon)
 end