Allow style setting postponement for all drawing methods + direct use of select path-painting operators

With this patch, the option to defer style setting implemented for lines() by https://github.com/MrRio/jsPDF/pull/203 is now available when calling all drawing methods. 

This patch makes it possible to use nested shapes to cut holes in paths, including allowing control of the ruleset used to determine which regions to fill. The latter functionality is implemented by permitting direct use of select PDF path-painting operators. 

## Example
````
var pdf = new jsPDF("portrait", "mm", "letter");
pdf.rect(125, 25, 50, 50, null);
pdf.rect(105, 5, 95, 95, 'f*');	
	
pdf.ellipse(55, 30, 5, 5, null);
pdf.ellipse(40, 20, 30, 20, 'f*');
````
Outputs:
![endresult](https://f.cloud.github.com/assets/857202/2401628/46380b42-aa18-11e3-9a58-d6cda7e11ff0.png)

 
Without this patch, the above code would output:
![prepatch](https://f.cloud.github.com/assets/857202/2401679/cc45460a-aa18-11e3-8529-2a80f4b8c043.png)