Apply tvg Array instead of std::vector
Also Fixed to compList in update() to passed by reference, not copying.
Also Fixed Composition Target memory leak
Here is the binary size result:
[libthorvg.so] 1785376 >> 1607416
[text] 121255 >> 118277
[data] 7792 >> 7736
[dec] 129119 >> 126085
This Array is promoted from SvgVector to use it widely in tvg.
It's similar with std::vector, we can use it instead of it.
Also, svg_loader replaced with it subsequently.
