FEATURE: Site settings defaults per locale

This change-set allows setting different defaults for different locales. 

It also:

- Adds extensive testing around site setting validation

- raises deprecation error if site setting has the default property based on env

- relocated site settings for dev and tests in the initializer

- deprecated client_setting in the site setting's loading process

- ensure it raises when a enum site setting being set

- default_locale is promoted to `required` category.

- fixes incorrect default setting and validation

- fixes ensure type check for site settings

- creates a benchmark for site setting

- sets reasonable defaults for Chinese

lib/site_settings/deprecated_settings.rb

@@ -0,0 +1,26 @@
+module SiteSettings; end
+
+module SiteSettings::DeprecatedSettings
+  DEPRECATED_SETTINGS = [
+    %w[use_https force_https 1.7]
+  ]
+
+  def setup_deprecated_methods
+    DEPRECATED_SETTINGS.each do |old_setting, new_setting, version|
+      define_singleton_method old_setting do
+        logger.warn("`SiteSetting.#{old_setting}` has been deprecated and will be removed in the #{version} Release. Please use `SiteSetting.#{new_setting}` instead")
+        self.public_send new_setting
+      end
+
+      define_singleton_method "#{old_setting}?" do
+        logger.warn("`SiteSetting.#{old_setting}?` has been deprecated and will be removed in the #{version} Release. Please use `SiteSetting.#{new_setting}?` instead")
+        self.public_send "#{new_setting}?"
+      end
+
+      define_singleton_method "#{old_setting}=" do |val|
+        logger.warn("`SiteSetting.#{old_setting}=` has been deprecated and will be removed in the #{version} Release. Please use `SiteSetting.#{new_setting}=` instead")
+        self.public_send "#{new_setting}=", val
+      end
+    end
+  end
+end