only read log configuration files ending with .yml or .yaml
fix compilation error on jdk8: ensure the compiler doesn't complain
"Merge pull request #7 from mping/jdk8\n\nfix compilation error on jdk8: ensure the compiler doesn't complain"
add decommission() method to Node and LifecycleComponent
implement full node deallocation
add disabled Lifecycle State
disable node if graceful_stop is_default
integrate deallocator in node.disable()/stop()
support graceful_stop.force setting in disable()

also removes graceful_stop.is_default as it cannot be
supported due to the limitation that jvm shutdown hooks
cannot be aborted.
make Deallocators aware of running deallocations
implemented primaries deallocation
verify min availability and and implement reallocate setting
added ES license headers
add graceful_stop settings as dynamic cluster settings
added more tests