Add followedBy, forEffect, mproduct and ifM

[pakoito]

Adds extra methods for Monad as requested in #69 (comment)

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@88446ce). Click here to learn what that means.
The diff coverage is 0%.

@@            Coverage Diff            @@
##             master     #212   +/-   ##
=========================================
  Coverage          ?   51.85%           
  Complexity        ?      200           
=========================================
  Files             ?       98           
  Lines             ?     2129           
  Branches          ?      262           
=========================================
  Hits              ?     1104           
  Misses            ?      917           
  Partials          ?      108

Impacted Files	Coverage Δ	Complexity Δ
...gory/src/main/kotlin/kategory/typeclasses/Monad.kt	64.61% <0%> (ø)	0 <0> (?)

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