Merge branch 'master' into ab-debian

Merge branch 'master' into ab-debian

* master: (69 commits)
  more README information
  added more information to README.md
  added common version options to all C programs; fixes #1927
  updated configs.signatures
  more information about metrics streaming; setting to cleanup orphan hosts on the master moved to netdata.conf
  updated configs.signatures
  update: add nsd plugin to python.d/README.md
  updated configs.signatures
  stream destination information
  Remove manager/status?XML=true URI Requirement
  added allmetrics API call to return JSON data; fixes #1910
  update: add netdata to "nsd" group
  fix: replace dot with _ at the dimension id
  added IPMI icon and info to main menu
  added new_pids counter to apps.plugin monitoring
  sensors states to line chart
  updated configs.signatures
  added freeipmi and fping to apps.plugin
  ExecutableService_class: uses find_binary method to find absolute path for command, other logic fixes
  modified:   python.d/nsd.chart.py
  ...