CookBook and Advanced Guide

[Kamirus]

Add literate ps cookbook guide with a table of contents on the top of the file

Write about:

• Custom Types (PG) - litPG - EForeign
• ShowM for custom PG functions - Any
• Overloaded binary expressions for Col and Aggr

[Kamirus]

Try to integrate with purescript-cookbook:

• provide one recipe in literate purescript here
• ask about literate recipes and adding postgresql to travis

[Kamirus]

Plan Change

• write an advanced guide on the topics above - with explanations
• try integration to integrate with purescript-cookbook when it's possible - write there some basic non-literate recipes