Remove dead tag_definition method
Remove dead tag_definition method

This was last used in 753126428bbdeed87ae232165cbecbd96801dccc.

Change-Id: Ifd4b05a8bddd6addfed9b39e28c8861f7f88fc9b
Reviewed-on: http://gerrit.causes.com/42569
Tested-by: jenkins <d95b56ce41a2e1ac4cecdd398defd7414407cc08@causes.com>
Reviewed-by: Shane da Silva <67fb7bfe39f841b16a1f86d3928acc568d12c716@brigade.com>

mzp/haml-lint,skateman/haml-lint