Declared-at comments in rewrites

[Jesper Mattsson]

The declared-at comments in generated code for rewrites contains an extra "@declaredat".

The rewriteTo method gets:

// Declared at @declaredat <PATH>

The rewriteRuleX methods get:

/**
 * @declaredat @declaredat <PATH>
 * @apilevel internal
 */

[Jesper Öqvist]

Improve declared at comments for rewrites

Fixed duplicate "declared at" in the source location comments for rewrites.

fixes #214

→ <<cset b76ad2fc4767>>