LPS-44354 Create BlogsSettings, move getters from BlogsUtil to it.

Replace invocations to BlogsUtil to obtaining the blogsSettings object and using its getters.
LPS-44354 Convert usage of PortletPreferences to BlogsSettings in configuration.jsp and init.jsp
LPS-44354 Move default values for blogs settings from code to portal.properties
LPS-44354 SF: Order properties to keep alphabetical order (even if it was not being followed for all properties already)
LPS-44354 Move configuration from Blogs to Blogs Admin portlet

This is done because the configuration is at the site level and should not be associated with a portlet which is added to a page any more, but to a portlet that is in site administration.
LPS-44354 Inline variables that no longer add much value
LPS-44354 SF