Merge pull request #1 from fumiyas/master

RGB values are intensity in the range of 0 to 100
gofmt
Fixed size
Use flag
Handle png/jpeg/gif
Add README.md
"./gosr -" should work as reading from stdin
Add Decoder
Add decoder application
Writer stdout in default
Update README.md
Quantization NGBA color model
Use image.Draw
Some image operation
Fix typo
gofmt
Usage
Transparent
Auto detect width/height
Add example application