Add gas costs for the different types of streams

[maxdesalle]

[PaulRBerg]

This would be also useful for user comms.

We have been frequently asked about the costs of creating streams.

[smol-ninja]

I've worked on this benchmark PR. I can add new rows to include gas usage for different stream shapes, and then we can copy paste from the tables to docs.

~But the question I would like to ask is: how many segments should be considered for the benchmark? 10, 50, 100?~ I've realized the answer is any number because if a shape is cheaper for 10 segments, it will also be cheaper for 100.

[andreivladbrg]

the exact shapes from the app and the docs are in the examples repo, we can simply add there a benchmark in the tests

[smol-ninja]

Makes sense to add them in the examples repo itself.

[andreivladbrg]

Merged 223e6b640cef1d223e0f018d6911aa4cf53e4348