TradeModuleV2 and GeneralIndexModuleV2

[richardliang]

Code Review Processes

New Feature Review

Before submitting a pull request for new review, make sure the following is done:

• Design doc is created and posted here: https://github.com/SetProtocol/STIPS/pull/12
• Code cleanliness and completeness is addressed via guidelines

README Checks

• [] README has proper context for the reviewer to understand what the code includes, any important design considerations, and areas to pay more attention to

Code Checks

• [] Add explanatory comments. If there is complex code that requires specific context or understanding, note that in a comment
• [] Remove unncessary comments. Any comments that do not add additional context, information, etc. should be removed
• [] Add javadocs.
• [] Scrub through the code for inconsistencies (e.g. removing extra spaces)
• [] Ensure there are not any .onlys in spec files

Broader Considerations

• [] Ensure variable, function and event naming is clear, consistent, and reflective for the scope of the code.
• [] Consider if certain pieces of logic should be placed in a different library, module

[bweick]

Commenting the diff for TradeModule and GeneralIndexModule