Provide option to remove glyph

[MelGrubb]

On my search form, I have several fields implemented as input groups, such as date ranges. These look like normal fields with a glyphicon button tacked to the right-hand side (see http://getbootstrap.com/components/#input-groups-basic). Short of overriding the entire text or template of the drop-down, there doesn't seem to be a way to ditch the downward chevron. I can still create an input group, of course, and I can create a right-aligned button with a downward chevron to match the rest of my form, but the main text of the button will still include its own chevron, spoiling the effect.