Automatic incrementing behavior on Ion-progress-bar

**Is your feature request related to a problem? Please describe.**
Currently, Ion-progressBar can only be shown/hidden and manually increment the values/buffer which is too much to do, unlike package like NProgress which come with so many properties. and works seamlessly with Vue Router / Vuex to automatically increment the progress in the ajax calls.

**Describe the solution you'd like**
Even if we could mimic the core functions seen in NProgress that in itself will be a great start...

**Describe alternatives you've considered**
Alternatives could be bringing NProgress onboard similar to swiper.js

**Additional context**
I have an active forum discussion regarding this on the ionic Forums.

The issue names Ion-progress-bar, NProgress, Vue Router/Vuex, and swiper.js but no implementation file or test. Start with the Ionic Forums discussion and compare the requested automatic behavior with NProgress; done requires an agreed scope for the progress-bar API and its integration behavior.

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