Fill in some undocumented entries (#356)

* Add permutations description

* Adjust grammar

* Update description of "num_mip_levels"

* Update "atlas_tile" and "blend_frames" property

Some properties had completely incorrect titles as well, those were fixed in this commit too.

* Update JSON UI schema

* Update item schema

* Update terrain_texture schema

* Update animations schema

* Update go_home.json

* Update textures schemas

source/behavior/items/format/minecraft.item.json

@@ -3,7 +3,7 @@
   "additionalProperties": false,
   "required": ["description"],
   "type": "object",
-  "description": "UNDOCUMENTED.",
+  "description": "An item definition.",
   "$comment": "UNDOCUMENTED",
   "title": "Item",
   "properties": {
@@ -11,7 +11,7 @@
       "additionalProperties": false,
       "type": "object",
       "title": "Description",
-      "description": "The description for this item",
+      "description": "The description for this item.",
       "$comment": "UNDOCUMENTED",
       "properties": {
         "identifier": {