Recreate favicon.ico.

Include a 32x32 and a 16x16 one.
Losslessly compress images.

Before: 18,6 KB (19.118 bytes)
After:  9,18 KB (9.405 bytes)
Update package.json.

Group dependencies and devDependencies together and sort them by name.
Merge pull request #53 from XhmikosR/master

Minor improvements