Optimize calcul of boundingbox

[throrin19]

Optimize phantom execution, memory and process childs for big svg file

[throrin19]

start optimizing by test all possible DOM manipulator mudules on nodeJS and, all of them do not work with getBoundingClientRect.

So, i optimize phantomJS usage and removed jquery inclusion but, if the svg is so big, nodejs crash and all phantomJS childs are not killed

[throrin19]

now changed engine. phantomJS has removed, jsdom not used, i calculate all of boundingbox. Except for Text, tspan and group. They are fixed.

For group, it's comming soon but for text, it's depend of police size, font, tspan positions, ...