Update node_group.rb

Inverted values for width / height
Merge pull request #36 from chuyyei/master

Update node_group.rb
Update README.md
CMYK channel order was incorrect. Fixes #37.
Version 1.3.1
Channels also seem to be out of order for Greyscale
Version 0.3.2
Parse full layer section divider block
Detect layer section divider in case that the info block is missing
Initial bit of organizing
Removal of old cruft and refactor of attr reader/accessors
Arrange exporting methods better
Fix numerous tree construction problems by parsing the lsdk key. Fixes #38.
File didn't get added
Version 1.3.3
Update README.md

Traversal method list was missing children
Merge branch 'master' into image_merging