In the notes, documented the syntaxes used for bound variables and let_in_.
In the notes, documented the syntaxes used for bound variables and let_in_.

era-platform/cene,rocketnia/era,rocketnia/era,era-platform/cene,rocketnia/era-cene,rocketnia/era-cene,rocketnia/era-cene,rocketnia/era,era-platform/cene