Consider adding a minify mode in CssPrinter

[alextekartik]

Currently the non pretty print output could be minify a little bit more

body { color: black; } div { }

could be compiled to

body{color:#000}

However currently it is compiled to

body { color: black; } div { }

Some optimizations

• remove spaces
• convert color to hex value (see pretty print convert colors to hexa while regular print does not #21)
• remove last ; in block
• remove empty block

If a minify option (or a new printer) is added it would have the following option

• minify: true|false
• line-length-max: NNN (where NNN is the maximum size of a line)