Detect initial values in fields declarations and throw a warning

[spalladino]

Setting an initial value for a field when declaring it does not work for proxies, since the value is set in the constructor (see #60 and #79 for more info).

contract MyContract {
  uint256 public hasInitialValue = 42;
}

Note that this is not a problem if the field is defined as constant.

We should detect these scenarios, in all contracts (plus their ancestors) and raise a warning. This warning should be run when adding pushing the contract.

[vs77bb]

Hi @spalladino Think I should put up a bounty here / elsewhere with the label bounty-worthy? Can do, if you think they're ready 👍

[spalladino]

Thanks a lot @vs77bb! We've been shuffling around priorities with @facuspagnuolo during these last few days, so we'll review the bounty-worthy labeled issues. We'll be removing the labels from those issues that we plan on tackling internally during the next 6 weeks, and add it to the ones that fell outside of the last planning, but would be nice-to-have nonetheless. We'll keep you posted!

[facuspagnuolo]

Hey @vs77bb! We already organized the issues and the bounty-worthy labels :)

[vs77bb]

@facuspagnuolo Just posted four bounties across those listed bounty worthy 🙂