function cameltoDash(string) {
    return string.replace(/([A-Z])/g, function($1) { return '-' + $1.toLowerCase(); });
  }
Provides a way for positioning tooltip & dropdown
arrows when using placement options beyond the standard
left, right, top, or bottom.

@param {element} elem - The tooltip/dropdown element.
@param {string} placement - The placement for the elem.