Issue #1161466: Use type, not orig_type to get custom field values.
* Modified the keyword density and image alt attribute rules to search all long-text fields, not just the body, and in the case of the alt attribute rule, to also search image fields as well as images inserted into text. * Both also search fields contained within Field Collections. * Also added two helper functions to seo_checker.module which are used in the above rules, and fixed a number of typos in help text, descriptions, etc.

Signed-off-by: Michael Ruoss <michael.ruoss@ufirstgroup.com>