LPS-45983 There are some jsps where we neeed to read the values from the request first and then the settings (like in configuration.jsp) and other places where we always want the value from the settings.

Conflicts:
	portal-web/docroot/html/portlet/document_library/init.jsp
LPS-45983 Adapt to changes in ParameterMapSettings constructor
LPS-45983 Generalize the DisplayContext concept and rely on it to extract logic out of JSPs and make handling of Settings easier

We make one display context per functional UI component that needs it. For example: one for actions, one for specialized actions for file entries, one for file entry lists, and so on.
LPS-45983 SF
LPS-45983 Remove duplicated code (the check is already done in init.jsp)
LPS-45983 Convert multi valued settings to String[] (instead of comma separated String)
LPS-45983 Declare multi valued settings in ConfigurationActionImpl so that SettingsConfigurationAction can handle them automagically
LPS-45983 Create DLConfigurationDisplayContext to decouple logic for configuration JSPs from logic for portlet's standard display JSPs
LPS-45983 Remove duplicated code (the check is already done in init.jsp)

Also inline unneeded variables in some configuration.jsp pages.
LPS-45983 Split DLConfigurationDisplayContext in two to decouple D&M configuration from D&M display configuration
LPS-45983 Add a method to get a localized key getting the locale from the given request
LPS-45983 Extract logic from D&M configuration.jsp to DLConfigurationDisplayContext
LPS-45983 Remove DLContext class because it's not clear what's its purpose and it's only used from DLFileEntryActionsDisplayContext (so we merge the two into DLFileEntryActionsDisplayContext)
LPS-45983 Extract logic from D&M display configuration.jsp to DLDisplayConfigurationDisplayContext
LPS-45983 Extract logic from media gallery configuration.jsp to IGConfigurationDisplayContext
LPS-45983 Remove some multi valued keys declarations that were incorrectly declared in some ConfigurationActionImpls (because the removed keys were not managed by the containing ConfigurationActionImpl)
LPS-45983 Move mime types setting from DLSettings to DLPortletInstanceSettings because it is not a configuration of the service but of the media gallery portlet
LPS-45983 Keep the same API in LanguageImpl and obtain the locale from the themeDisplay
LPS-45983 Remove getPortletInstanceSettings method from portletDisplay and make sure that we always obtain dlPortletInstanceSettings the same way
LPS-45983 Use populate and order