feat(abide): add validator-specific error messages

feat(abide): add validator-specific error messages

Now you can add different error messages for each validator using the
`[data-form-error-on]` attribute.

<input required type="email">
<span class="form-error" data-form-error-on="required">Required</span>
<span class="form-error" data-form-error-on="pattern">Invalid</span>

BREAKING CHANGE: `Foundation.Abide#validateText()` no longer checks if
the input is required. Use the `Foundation.Abide#requiredCheck()` method
for that.

Closes #10799