Remove html5_validators gem

Closes #367

app/models/billing/price.rb

@@ -2,8 +2,6 @@ module Billing
   class Price < ActiveRecord::Base
     include Concerns::Billing::Price::Expirable
 
-    self.auto_html5_validation = false
-
     belongs_to :zone, class_name: 'DNS::Zone', required: true
     has_many :account_activities
 

app/models/concerns/disable_html5_validation.rb

@@ -1,9 +0,0 @@
-module DisableHtml5Validation
-  extend ActiveSupport::Concern
-
-  class_methods do
-    def auto_html5_validation
-      false
-    end
-  end
-end

app/models/deposit.rb

@@ -2,7 +2,6 @@ class Deposit
   include ActiveModel::Validations
   include ActiveModel::Conversion
   extend ActiveModel::Naming
-  include DisableHtml5Validation
 
   attr_accessor :description, :registrar, :registrar_id
   attr_writer :amount

app/models/depp/contact.rb

@@ -1,7 +1,6 @@
 module Depp
   class Contact
     include ActiveModel::Model
-    include DisableHtml5Validation
 
     attr_accessor :id, :name, :email, :phone, :org_name,
       :ident, :ident_type, :ident_country_code,

app/models/depp/domain.rb

@@ -2,7 +2,6 @@ module Depp
   class Domain
     include ActiveModel::Conversion
     extend ActiveModel::Naming
-    include DisableHtml5Validation
 
     attr_accessor :name, :current_user, :epp_xml
 

app/models/depp/keyrelay.rb

@@ -1,6 +1,5 @@
 module Depp
   class Keyrelay
-    include DisableHtml5Validation
     attr_accessor :current_user, :epp_xml
 
     def initialize(args = {})

app/models/depp/user.rb

@@ -3,7 +3,6 @@ module Depp
     include ActiveModel::Validations
     include ActiveModel::Conversion
     extend ActiveModel::Naming
-    include DisableHtml5Validation
 
     attr_accessor :tag, :password, :pki
 

app/models/dns/zone.rb

@@ -1,7 +1,5 @@
 module DNS
   class Zone < ActiveRecord::Base
-    self.auto_html5_validation = false
-
     validates :origin, :ttl, :refresh, :retry, :expire, :minimum_ttl, :email, :master_nameserver, presence: true
     validates :ttl, :refresh, :retry, :expire, :minimum_ttl, numericality: { only_integer: true }
     validates :origin, uniqueness: true