Bug description:

No possibility to set invalid Datepicker values (to display inside input field),
even if ng-model-options="{allowInvalid: true}".
As I suppose Timepicker bahaviour is the same.

If validation of entered value is so strict, should be easy possibility to override it.

Link to minimally-working plunker that reproduces the issue:

http://plnkr.co/edit/ltjUZ8ZTGZS2T4YVI7YN?p=preview

After click of [SET: now-7d] button I'd like to see "now-7d" inside input field.
In one of previous version (eg. 0.14) it worked as expected.

Version of Angular, UIBS, and Bootstrap

Angular: 1.5.7
UIBS: 1.3.3
Bootstrap: 3.3.6