fixes #678
Added the MemoryMonitor
Moved the startup of the memorymonitor to node.start
Upgraded the memory monitor to health monitor (so include cpu) also it is on by default
Minor logging improvement
Merge pull request #701 from pveentjer/improvement/3.x/memory-monitor

Improvement/3.x/memory monitor
Merge pull request #697 from sancar/fix/3.1/issue678

fixes #678