more eclipse 4 adjustments
grouped the deprecated extensions
remove unused menu extensions
1363: save runtime preferences under a different key
clean up a bit usage of "org.erlide.core" references
rename BackendUtil to RpcSiteFactory and make it API
refactor ErlideUIPlugin
code cleanup
move some classes from runtime to backend
make Builder helpers public
remove bad dependency in ISourceUnit
cleanup ProblemsData
cleanup
cleanup
cleanup events
Merge branch 'pu' into startup
refactor backend plugin activator
cleanup activator
cleanup
IErlRuntime cleanup