Massive refactoring to clean up models

* Tweak style of quantity label in output box to be more visible
* Move data files for all mods under a directory for the specific
  version of the mod
* Add a `silent` property to the base model to prevent models which
  shouldn't be observed from emitting events
* Change the term "itemSlug" to just "slug" across the board
* Change all models so that they don't require their parent in their
  constructors and so that they don't automatically add themselves to
  their parents lists
* Remove a bunch of unnecessary event triggering
* Tighten up access to various lists of children across all models
* Refactor the guts of the V2 parser into an abstract base class so
  it can be used for other parsers in the future
* Remove a number of unused methods

src/scripts/models/mod_pack.coffee

@@ -16,35 +16,18 @@ ModVersionParser     = require './mod_version_parser'
 module.exports = class ModPack extends BaseModel
 
     constructor: (attributes={}, options={})->
-        attributes.modVersions ?= []
         super attributes, options
 
+        @_modVersions = []
+
     # Public Methods ###############################################################################
 
-    addModVersion: (modVersion)->
-        if modVersion.modPack isnt this then throw new Error "the mod version must be associated with this mod pack"
-        return if @modVersions.indexOf(modVersion) isnt -1
-
-        @modVersions.push modVersion
-        @trigger Event.add, modVersion, this
-
-        @modVersions.sort (a, b)-> a.compareTo b
-        @trigger Event.sort, this
-        @trigger Event.change, this
-        return this
-
-    enableModsForItem: (name)->
-        for modVersion in @modVersions
-            continue if modVersion.enabled
-            if modVersion.hasRecipe name
-                modVersion.enabled = true
-
-    findItem: (itemSlug, options={})->
+    findItem: (slug, options={})->
         options.includeDisabled ?= false
 
-        for modVersion in @modVersions
+        for modVersion in @_modVersions
             continue unless modVersion.enabled or options.includeDisabled
-            item = modVersion.items[itemSlug]
+            item = modVersion.findItem slug
             return item if item?
 
         return null
@@ -53,9 +36,9 @@ module.exports = class ModPack extends BaseModel
         options.includeDisabled ?= false
         slug = _.slugify name
 
-        for modVersion in @modVersions
+        for modVersion in @_modVersions
             continue unless modVersion.enabled or options.includeDisabled
-            item = modVersion.items[slug]
+            item = modVersion.findItem slug
             return item if item?
 
         return null
@@ -63,12 +46,12 @@ module.exports = class ModPack extends BaseModel
     findName: (slug, options={})->
         options.includeDisabled ?= false
 
-        for modVersion in @modVersions
+        for modVersion in @_modVersions
             continue unless modVersion.enabled or options.includeDisabled
             name = modVersion.findName slug
             return name if name
 
-        return slug
+        return null
 
     findItemDisplay: (slug)->
         result = {}
@@ -76,39 +59,50 @@ module.exports = class ModPack extends BaseModel
         if item?
             result.modSlug    = item.modVersion.slug
             result.modVersion = item.modVersion.version
-            result.itemSlug   = item.slug
+            result.slug   = item.slug
             result.itemName   = item.name
         else
             result.modSlug    = _.slugify DefaultModVersions[0].name
             result.modVersion = DefaultModVersions[0].version
-            result.itemSlug   = slug
+            result.slug   = slug
             result.itemName   = @findName slug, includeDisabled:true
 
         result.iconUrl = Url.itemIcon result
         result.itemUrl = Url.item result
         return result
 
-    hasRecipe: (name, options={})->
-        options.includeDisabled ?= false
-
-        for modVersion in @modVersions
-            continue unless modVersion.enabled or options.includeDisabled
-            return true if modVersion.hasRecipe name
-
-        return false
-
     isValidName: (name, options={})->
         options.includeDisabled ?= false
 
         slug = _.slugify name
-        for modVersion in @modVersions
+        for modVersion in @_modVersions
             continue unless modVersion.enabled or options.includeDisabled
             name = modVersion.findName slug
             return true if name
 
         return false
 
+    # Property Methods #############################################################################
+
+    addModVersion: (modVersion)->
+        return if @_modVersions.indexOf(modVersion) isnt -1
+
+        @_modVersions.push modVersion
+        @trigger Event.add, modVersion, this
+
+        @_modVersions.sort (a, b)-> a.compareTo b
+        @trigger Event.change, this
+
+        return this
+
+    eachModVersion: (callback)->
+        for modVersion in @_modVersions
+            callback modVersion
+
+    getModVersions: ->
+        return @_modVersions[..]
+
     # Object Overrides #############################################################################
 
     toString: ->
-        return "ModPack (#{@cid}) {modVersions:#{@modVersions.length} items}"
+        return "ModPack (#{@cid}) {modVersions:#{@_modVersions.length} items}"