v0.3.1

Clapeyron v0.3.1

Diff since v0.3.0

Model fixes;

• WSRule
• MonomerIdeal
  new functions:
  assoc_site_matrix(model::Union{SAFTModel,CPAModel},V,T,z) to instantiate the association matrix
  ReidIdeal(model::JacobianIdeal) to obtain a Reid ideal model from a Joback Ideal model
  faster crit_pure on cubics

Merged pull requests:

• Update Electrolyte Branch (#59) (@pw0908)
• Merging Documentation Modifications (#60) (@pw0908)
• GERG rewrite (#61) (@longemen3000)
• made PR autodiffable, like RK (#64) (@TJP-Karpowski)
• Docs, Assoc Matrix (#66) (@longemen3000)