code: function(options){
  	this.dom = [];
  	this.fillColor='black';
  	this.strokeColor='black';
  	this.strokeWidth=1;
  	this.unit='mm';
  	this.width=100;
  	this.height=100;
  
  	for(var optionName in options){
  		this[optionName]=options[optionName];
  	}
  }
docs: This class create the SVG stage.
  Options can be:
  * fillColor: color
  * strokeColor: color
  * strokeWidth: number (defaults to 1)
  * unit: ['mm','cm','px','in'] (defaults to mm)
  * width: number or a function
  * height: number or a function