[TASK]: futures parameter caching for gas optimisation

[artdgn]

Futures is calling external storage contract a LOT which ends up costing a lot. We can probably do much better. Some options:

• Cache some of the values on the market contract.
• Store the values themselves on the contract instead of fetching them from external contract.
• Maybe something else..

[artdgn]

Parameters caching and batching was not helpful, but reducing size of storage variables was somewhat helpful (20% reduction): https://github.com/Synthetixio/synthetix/pull/1614

[artdgn]

Done in https://github.com/Synthetixio/synthetix/pull/1614