FghjNode.opEquals

import fghj;
auto text = `{"foo":"bar","inner":{"a":true,"b":false,"c":"32323","d":null,"e":{}}}`;
auto root1 = FghjNode(text.parseJson);
auto root2= FghjNode(text.parseJson);
assert(root1 == root2);
assert(root1["inner"].children.remove("b"));
assert(root1 != root2);