feat(mint): add DevelopmentFund to block rewards

[giunatale]

Closes #809

Currently rewards are sent to addresses in the weighted list directly, no locking/vesting mechanisms. Anything to be done around that is TBD, perhaps we might want to add an issue to track this?

[codecov]

Codecov Report

Merging #839 (06fddec) into develop (f3f4098) will increase coverage by 0.01%.
The diff coverage is 16.23%.

@@             Coverage Diff             @@
##           develop     #839      +/-   ##
===========================================
+ Coverage    10.40%   10.41%   +0.01%     
===========================================
  Files          325      325              
  Lines        75688    76047     +359     
===========================================
+ Hits          7872     7917      +45     
- Misses       67628    67940     +312     
- Partials       188      190       +2     

Impacted Files	Coverage Δ
x/mint/types/mint.pb.go	0.52% <0.35%> (-0.06%)	⬇️
x/mint/types/params.go	8.46% <12.50%> (-0.63%)	⬇️
x/mint/simulation/genesis.go	97.72% <100.00%> (+1.17%)	⬆️
x/mint/simulation/params.go	100.00% <100.00%> (ø)
x/campaign/simulation/store.go	81.08% <0.00%> (-3.38%)	⬇️

[lumtis]

Currently rewards are sent to addresses in the weighted list directly, no locking/vesting mechanisms. Anything to be done around that is TBD, perhaps we might want to add an issue to track this?

Yes, I created this one #840 if you have thoughts to share

[lumtis]

I think we can add some sample addresses in config.yml param for the module to try out the feature locally. Eventually reusing addresses we have in accounts section

DistributeMintedCoins is a sensitive component. We should introduce unit tests for it. Eventually creating a separate issue for it depending on the complexity.

[lumtis]

LGTM👍