Decoupled projects: Contract changes

[topocount]

Addresses #1875 and #1897

This PR adds functions to the projects contract for:

• creating decoupled projects that can include an IPFS hash
• creating and modifiying issues that don't yet contain bounties

This PR also contains

• gas optimizations to allow these issues to fit in the contract
• the removal of the standard bounties bytecode check to make room for these features, since isContract should be sufficient

Note

• [x] merge #1908 before this PR

[rkzel]

Specification suggests that there should be a fuction to edit project as well as add/remove. Editing will involve only replacing ipfs hash saved in_projectData, so all we need is a simple function like this:

    function updateRepo(bytes32 _repoId, string _repoData) external auth(....?)
     {
        require(isRepoAdded(_repoId), ERROR_REPO_MISSING);
        uint rowToUpdate = repos[_repoId].index;
        repoIndex[repoIndexLength] = _repoId;
        repos[rowToUpdate].repoData = _repoData;
        emit Repo....?
    }

Probably a new right and event to emit need to be added as well - what do you think, @topocount ? Alternatively if it's too complicated for current timeline, maybe we leave it for now and not allow editing projects at all?

[topocount]

Changed base branch to merge, to properly see the exact changes going on here

We're working out of the https://github.com/AutarkLabs/open-enterprise/tree/decentralized-project-integration banch, and this branch has already been merged in there. I'll make your requested changes in there and redirect https://github.com/AutarkLabs/open-enterprise/tree/issue-querying to that branch as well.

[topocount]

This branch has been merged into PR #1941. The review above has been addressed there