Add granularity options to pruning state

[jgimeno]

Closes: #5684

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[jgimeno]

Even that it does not break back compatibility unless they use the new flags the new way to call SetPruning from gaia for example is:

baseapp.SetPruning(server.GetPruningOptionsFromFlags()),

instead of

baseapp.SetPruning(store.NewPruningOptionsFromString(viper.GetString("pruning"))),

So I don't know if it is worth it to deprecate the old NewPruningOptionsFromString, and later make it private. Ideas?

[fedekunze]

LGTM. Minor comments only

[alexanderbez]

minor nitpicks, but otherwise LGTM. Great job @jgimeno 👍

[alexanderbez]

ACK ☕️

[codecov]

Codecov Report

Merging #5709 into master will increase coverage by 0.22%.
The diff coverage is 27.16%.

@@            Coverage Diff            @@
##           master   #5709      +/-   ##
=========================================
+ Coverage   35.47%   35.7%   +0.22%     
=========================================
  Files         333     335       +2     
  Lines       32604   32695      +91     
=========================================
+ Hits        11566   11673     +107     
+ Misses      19816   19790      -26     
- Partials     1222    1232      +10

Impacted Files	Coverage Δ
simapp/test_helpers.go	0% <0%> (ø)	⬆️
x/staking/keeper/val_state_change.go	65.03% <100%> (ø)	⬆️
x/staking/keeper/keeper.go	60% <100%> (+11.51%)	⬆️
x/staking/keeper/validator.go	79.57% <100%> (ø)	⬆️
x/staking/keeper/delegation.go	75.66% <100%> (+0.89%)	⬆️
x/staking/keeper/slash.go	71.53% <100%> (ø)	⬆️
version/command.go	77.77% <80%> (ø)
version/version.go	100% <0%> (ø)
... and 4 more