Replace "new Meteor.Collection" by @_initModel in models

packages/rocketchat-lib/package.js

@@ -12,6 +12,7 @@ Package.onUse(function(api) {
 	api.use('reactive-dict');
 	api.use('coffeescript');
 	api.use('random');
+	api.use('check');
 	api.use('underscore');
 	api.use('underscorestring:underscore.string');
 

packages/rocketchat-lib/server/models/Messages.coffee

 RocketChat.models.Messages = new class asd extends RocketChat.models._Base
 	constructor: ->
-		@model = new Meteor.Collection 'rocketchat_message'
+		@_initModel 'message'
 
 		@tryEnsureIndex { 'rid': 1, 'ts': 1 }
 		@tryEnsureIndex { 'ets': 1 }, { sparse: 1 }

packages/rocketchat-lib/server/models/Reports.coffee

 RocketChat.models.Reports = new class asd extends RocketChat.models._Base
 	constructor: ->
-		@model = new Meteor.Collection 'rocketchat_reports'
+		@_initModel 'reports'
 
 
 	# INSERT

packages/rocketchat-lib/server/models/Rooms.coffee

 RocketChat.models.Rooms = new class asd extends RocketChat.models._Base
 	constructor: ->
-		@model = new Meteor.Collection 'rocketchat_room'
+		@_initModel 'room'
 
 		@tryEnsureIndex { 'name': 1 }, { unique: 1, sparse: 1 }
 		@tryEnsureIndex { 'u._id': 1 }

packages/rocketchat-lib/server/models/Subscriptions.coffee

 RocketChat.models.Subscriptions = new class asd extends RocketChat.models._Base
 	constructor: ->
-		@model = new Meteor.Collection 'rocketchat_subscription'
+		@_initModel 'subscription'
 
 		@tryEnsureIndex { 'rid': 1, 'u._id': 1 }, { unique: 1 }
 		@tryEnsureIndex { 'u._id': 1, 'name': 1, 't': 1 }, { unique: 1 }

packages/rocketchat-lib/server/models/_Base.coffee

 RocketChat.models._Base = class
+	_baseName: ->
+		return 'rocketchat_'
+
+	_initModel: (name) ->
+		check name, String
+
+		@model = new Meteor.Collection @_baseName() + name
+
 	find: ->
 		return @model.find.apply @model, arguments
 

packages/rocketchat-oembed/server/models/OEmbedCache.coffee

 RocketChat.models.OEmbedCache = new class asd extends RocketChat.models._Base
 	constructor: ->
-		@model = new Meteor.Collection 'rocketchat_oembed_cache'
+		@_initModel 'oembed_cache'
 
 
 	# FIND ONE

packages/rocketchat-statistics/server/models/MRStatistics.coffee

 RocketChat.models.MRStatistics = new class asd extends RocketChat.models._Base
 	constructor: ->
-		@model = new Meteor.Collection 'rocketchat_mr_statistics'
+		@_initModel 'mr_statistics'
+
 
 	# FIND ONE
 	findOneById: (_id, options) ->