Gas optimization

[mrsmkl]

Description

What could be removed

• some parameters from conditions can be removed, this will make creating agreements at least 50% cheaper
• in theory creating an agreement would need only one or perhaps no on-chain variables, but fulfilling the conditions still requires gas so there's probably no point in optimizing it so much
• access agreement when condition creation is optimized: 610k (originally 1040k)
• creating access agreement when agreement creation is optimized: 300k (also removed condition ids from storage)
• lock 120k + approve 40k
• fulfill escrow 100k
• access condition 90k
• snark proof: 300k
• creating condition: 110k (originally 230k)

Questions:

• should we keep condition ids in agreements (otherwise can be checked from events)
• do we need provenance in storage or are events enough?

Adds a DoS protection for agreements similar to DIDs.

Is this PR related with an open issue?

Related to Issue #236

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• Follows the code style of this project.
• Tests Cover Changes
• Documentation

Funny gif

[aaitor]

It's looking good. There is pending a comments clean up and removing unused stuff.
That would lead to break compatibility.
I suggest apply these changes and merge into a 2.x contracts branch. Apply also the version 2.0.0-rc0 or 1.99.0

[aaitor]

LGTM!