Record if authorization identifier is delimited or not

[kokosing]

This issue comes from discussion: #289 (comment)

Per the standard, an authorization identifier is just a regular identifier, so the common rules for matching identifiers apply.

<authorization identifier> ::=
    <role name>
  | <user identifier>

<role name> ::=
  <identifier>

<user identifier> ::=
  <identifier>

Given two identifiers, A and B, the rules are, basically:

• If A and B are delimited, they are equivalent if they are equal
• If A is delimited and B is not, they are equivalent if A is equal to the capitalized form of B. Viceversa if B is delimited and A is not.
• If A and B are both not delimited, they are equivalent if their capitalized forms are equal.

So, this class needs to record whether the name was originally in SQL as a delimited identifier or not.

This class refers to PrestoPrincipal.

[martint]

Related to #17