Rename decimail to decimals

[banshee]

Broke this out of junious's PR

[codecov[bot]]

Codecov Report

Merging #3355 (ad8d00d) into future/peggy2 (fe6642d) will not change coverage. The diff coverage is 75.00%.

@@              Coverage Diff               @@
##           future/peggy2    #3355   +/-   ##
==============================================
  Coverage          48.28%   48.28%           
==============================================
  Files                169      169           
  Lines              14979    14979           
==============================================
  Hits                7232     7232           
  Misses              7315     7315           
  Partials             432      432           

Impacted Files	Coverage Δ
cmd/ebrelayer/txs/relayToEthereum.go	0.00% <0.00%> (ø)
x/oracle/keeper/prophecy.go	84.53% <100.00%> (ø)