+ add methods toString/toXml/toJSON in Svg class
+ add jsdoc
Merge remote-tracking branch 'origin/master'
+ add function findByType in svg and group classes
@ edit toXml, toJSON and toString function to add possibility to omit transform param
+ applye matrix to rect and convert this into polygon
+ test on Rotate
+ add applyMatrix to polygon and tspan
@ change applyMatrix function. Remove return and call callback function