net/http #5

Hi,

When importing gfx in a Go project, it also drags along the net/http package, which significantly increases the size of resulting executables, even if net/http is not specifically used.

Could net/http please be removed from this package?

From a security point of view, I think that some users would also be happy that ie. utilities that uses this gfx does not need net/http (even though it's easy to audit that there is nothing questionable happening).

I forked the gfx package to avoid using net/http in both Orbiton and png2svg, only to reduce the executable size.

Thanks for considering the feature request, and thanks for creating the gfx package!