Flow graphs serialization

[carolhmj]

Changes

• This PR adds "serialize" and "parse" functions to the flow graph, which work similarly to the other serialization functions we have in the framework
• It also standardizes the construction of the blocks, with a generic construction parameters interface (which has a name for all blocks), and a generic "configure" function that configures blocks according to its construction parameters. This is used, for example, in the "multiGate" block to configure how many outputs the block has.
• It also adds a getClassName function for all blocks (and I'm very sorry for the size the PR ended up with 😢 )
• It also adds all the blocks to the class register
• Removed the CustomFunctionBlock since it's not on the spec and I was just using it for tests. Instead now I'm using the Log block and mocking the console.log function

Examples

• Serialize: #KSTQJU#3
• Parse: #CVDC94#2

[bjsplat]

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[bjsplat]

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[bjsplat]

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[RaananW]

I have a few general comments regarding architecture -

1. It seems like every class has the same string repeated 4 times. It could be a const defined outside of the class (that is not exported).
2. The config = { name: ... } could backfire if someone will pass a different configuration object without a name.
3. Why is the name needed, why is getClassName not enough?
4. Something we have discussed a long time ago - to make the classes a little smaller, we could remove the FlowGraph part of those to make them a little shorter.

[RaananW]

Sorry, a few other questions that came out over the weekend

Parse should be, in general, a static function. I noticed that you have a class member parse functions. Is that deliberate? does that mean that you need to first create an instance of this class and only then pass the serialized object to parse it?

Also - the idea with making the name a little smaller was not only for the variable name. Changing FlowGraph to FG (for example, or maybe even FlowGraphBlock = FGB) with many nodes will save a lot of space on the serialized JSON.

[RaananW]

Just a few questions and small nits, otherwise LGTM