Epochs Module

[ramacarlucho]

Closes: #XXX

Description

Add osmosis epochs module.

WIP: currently cli_test.go is failing.
The Genesis state is not beeing correctly initialized in the tests, so the client cant find any of the created epochs.

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For contributor use:

• Targeted PR against correct branch (see CONTRIBUTING.md)
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the module structure standards.
• Wrote unit and integration tests
• Updated relevant documentation (docs/) or specification (x/<module>/spec/)
• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• Re-reviewed Files changed in the Github PR explorer

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For admin use:

• Added appropriate labels to PR (ex. WIP, R4R, docs, etc)
• Reviewers assigned
• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)

[codecov]

Codecov Report

Merging #183 (fcd6062) into main (4fff189) will decrease coverage by 0.25%.
The diff coverage is 71.01%.

❗ Current head fcd6062 differs from pull request most recent head 4d5db04. Consider uploading reports for the commit 4d5db04 to get more accurate results

@@            Coverage Diff             @@
##             main     #183      +/-   ##
==========================================
- Coverage   72.61%   72.35%   -0.26%     
==========================================
  Files          24       33       +9     
  Lines        1727     2040     +313     
==========================================
+ Hits         1254     1476     +222     
- Misses        421      501      +80     
- Partials       52       63      +11     

Impacted Files	Coverage Δ
x/epochs/handler.go	20.00% <20.00%> (ø)
x/epochs/keeper/grpc_query.go	38.88% <38.88%> (ø)
x/epochs/module.go	51.61% <51.61%> (ø)
x/epochs/client/cli/query.go	63.15% <63.15%> (ø)
x/epochs/keeper/keeper.go	84.61% <84.61%> (ø)
x/epochs/keeper/epoch.go	87.50% <87.50%> (ø)
app/app.go	80.66% <100.00%> (+0.52%)	⬆️
x/epochs/genesis.go	100.00% <100.00%> (ø)
x/epochs/keeper/abci.go	100.00% <100.00%> (ø)
x/epochs/keeper/hooks.go	100.00% <100.00%> (ø)

[lgtm-com]

This pull request introduces 1 alert when merging 473faa8 into 4fff189 - view on LGTM.com

new alerts:

• 1 for Useless assignment to local variable

[fedekunze]

LGTM