Math, appending, and more

Syntax:

Node += val

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If you used pyndb, you probably had to do something like this:

x = PYNDatabase({})
x.set("a", 1)
x.set("a", x.a.val + 1)

Let's be real here, this SUCKS. pyntree does it better:

x = Node()
x.a = 1
x.a += 1

Wow, that's infinitely simpler and less painful, right?!