Adds a new compiler option `validateNoUseBeforeDefine`, which enables a
post-codegen pass to validate that there are no usages of values before they are
defined (which causes a ReferenceError at runtime). This can occur when a value
is accessed when its in the TDZ (temporary dead zone), after the hoisted
_declaration_ but before the variable is defined:
```javascript
function foo() {
x; // x is in the TDX here: the binding from the subsequent statement is
hoisted, but x is not yet defined.
let x;
}
```
* The validation is off by default, but enabled in transform-test
* The validation crashes compilation, rather than bailout, because the code has
already been mangled and we can't roll back at the point the validation runs.
* The validator uses ESLint's no-use-before-define rule by printing the program
to source and then configuring ESLint to use Hermes parser.
* transform-test now supports tests prefixed with "error." to indicate tests for
which compilation is expected to crash (not just bailout), and the expect file
includes the error message.
