Add PUT to generic object definitions API

[jntullo]

Add the ability to use PUT to edit a generic object definition (cc: @AparnaKarve)

Example usage

PUT /api/generic_object_definitions/:id
{
   "name" : "updated name",
   "description": "updated description"
}

@miq-bot add_label enhancement
@miq-bot assign @abellotti

[miq-bot]

Checked commit jntullo@2ebd1be with ruby 2.2.6, rubocop 0.47.1, and haml-lint 0.20.0
1 file checked, 0 offenses detected
Everything looks fine. 🍰

[abellotti]

This looks good to me @jntullo, thanks for the enhancement.

@AparnaKarve are you ok with this, can I go ahead and merge it ? Thanks.

[AparnaKarve]

@abellotti Yes, this works great!

@jntullo Thank you!

[abellotti]

LGTM!!