fix(input-directive): non-date input did not set ng-valid after model…

… is set to valid date

fix #448 edge case for non-date input

fix(input-directive): input does not remove ng-invalid with valid mod…

…el value

When the user enters an invalid date (i.e. past date or total non-sense) the input validates and
adds 'ng-invalid' to the input. Then the model is updated to a valid input (i.e. not through the
input but rather the date-picker or an async call returning a value) the directive correctly sets
`ng-valid` on the input. Prior to this fix, the input would not re-validate when changes to the
model happened.

Fix #448

feat: add support for Angular 8

BREAKING CHANGE: the API for the @ViewChild annotation change in Angular 8 and this component uses
the new syntax.

feat: add attributes to improve e2e testing

If you were depending on the existance of date values in the classes of buttons, or other similar
changes, your code will break after upgrading. I did not consider those classes part of the public
API so I am not listing this as a breaking change.

fix: maximum call stack size exceeded

fix #440

fix: fix maximum call stack size exceeded with `ng build --prod`

Fix #440

feat(app): add configurator functionality to home page

this will show when running `npm start`

fix(aot): AOT build failing after adding string data support

ERROR in ../angular-bootstrap-datetimepicker/angular-bootstrap-datetimepicker.ts(104,9): Error
during template compile of 'DlDateTimePickerStringModule’. Function calls are not supported in
decorators but 'localeData' was called.

Fixes #429

feat(DlDateAdapterString): add support for string date in model

Also updated docs and simplified release configuration in package.json

Fixes #412

ci(package.json): Update release configuration to fix npm publishing …

…failure