Add component to phrases/e-mail templates

Right now the only way to get a sub-set of phrases/e-mail templates is to filter/export them by module. But what if within a same module phrases/e-mail templates then are also logically grouped.

For example all phrases, related to "tags" functionality might not always have "tag" word in them and some of them, even having "tag" word in the label might be not related to "tags" functionality in either way.

If phrase/e-mail event is shared between several components, then I think these is no much need to specify a component at all.