Enable '@openapi' annotation for spec comments

[jessevdp]

Since the specification has been renamed to OpenAPI I thought it would be appropriate to allow for @openapi annotation in addition to using @swagger.

/**
 * @openapi
 * /example:
 *   get:
 *     summary: "Get all"
 *     responses:
 *       200:
 *         description: OK
 */

I only changed a single if statement, I have no clue if this change would impact other area's of the code as well. If additional changes are required, please point me in the right direction.

[kalinchernev]

Hi @jessevdp I think your change will be quite enough to be honest without digging too deep.
Please update to latest master as I just cleaned up some linting (and perttier) rules and test setup, etc. Should be easier to contribute your changes.

Please add a test for the new feature. You can start off any of the simple examples here Please name it accordingly. Having a passing test for the new feature will suffice for a merge :)

[Uzlopak]

I created a corresponding PR with the change and with a simple test. Would be cool to merge "my" PR soon, as I would like to have potential replacement for openapi-jsdoc.

[kalinchernev]

Followed up on the one with the tests and it's merged.
Thank you @jessevdp and @Uzlopak!