Default settings provider implementation
convert alternateSettings attribute to extension 
selection, with backward compatibility
help messages
implement submit() to store settingsProvider configuration
move Maven SettingsProvider to core
disable file path validation
add GlobalSettingsProvider as new EP
implement readResolve() for backward comp.
fix instanziation from json
extend correct descriptor
note about TODO for next refactoring
use drop down selector to save space in the UI
TODO: remove old selectors
add PluginUpdateMonitor to inform administrators about required updates
fix PluginUpdateMonitor rendering issue
simplify interface of new EP
change RedeployPublisher to use new EP to get settings.xml
change MavenUtil to use new EP to get settings.xml
only one entry per plugin
deprecating old settings stuff
use path returned by SettingsProvider