Add a Case Sensitive Condition to Entity Query

Problem/Motivation

The default Condition and its pgsql child do not allow for a case sensitive entity query.

MySQL doesn't do this by default, we need something like '= BINARY'.
In PostgreSQL, we actually disable it. And it doesn't support the mysql fashion.

Proposed resolution

Add a condition for case sensitive queries. Right now this blocks things like #2633242: Process plugin for importing/creating terms by name, which is trying to replicate the Case Sensitive creation of Taxonomy terms, similar to D7.

Remaining tasks

Do it.

User interface changes

API changes

Adds an additional condition type for entity queries.

Data model changes