Nearest neighbor finder

Pull request #31: Documentation

Merge in EOSC-RS/nearest-neighbor-finder from documentation to master

* commit 'cf1ef56ccf24ab61c0c4a100bdb23993038165c5':
  docs update
  docs fix
  remove unfinished docs
  finished docs required for 15.11
  updated docs
  docs introduction update
  updated troubleshooting
  documentation update