fix version number & package name
Merge branch 'anthpack-v2' into release/v2.0.1

* anthpack-v2:
  change preview picture size
  parallel 3 preview pic composite
  change gmagick.composite signature
  change gmagick.mosaic signature
  change gmagick.addText signature
  change gmagick.resize signature
  refactoring gmagick.composite
  refactoring gmagick.mosaic
  refactoring gmagick.addText
  remove gmagick.crop
  refacoring gmagick.resize
  remove gmagick.generate
  remove gmagick.size
  improve format performance
  fix travis
  test picturre quality
update package.json
lower case package name