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
cleanup events
Merge branch 'pu' into startup
refactor backend plugin activator
cleanup activator
cleanup
IErlRuntime cleanup
change timings for polling runtime
add jrugged library
wip IRpcSite
Merge branch 'startup' into pu