Extend Datepicker's bsDaterangepicker

[joelmuskwe]

Is your feature request related to a problem? Please describe.

• Can you please extend the bsDaterangepicker such that when you enable timePicker upon selecting date range it won't close automatically to enable one to also set the time they want.
• Also extend the bsDaterangepicker such that we can be able to specify the hourStep and minuteStep to be used if the timePicker is enabled.

Describe the solution you'd like

• make the following property keepDatepickerOpened: true close for bsDaterangepicker when timePicker is enabled.
• allow hourStep and minuteStep to work with bsConfig for bsDaterangepicker when withTimepicker is enabled or change the withTimepicker to be an object rather than a Boolean such that we can pass a configuration like:
  [bsConfig]="{ withTimepicker: { hourStep: 1, minuteStep: 1 }, }"