Improve usability of TruncatableComponet

[atarix83]

Is your feature request related to a problem? Please describe.
Currently the TruncatableComponent has the aim of truncate long text and make it extendible/collapsible. We have received several feedback that detect it not so user friendly. Indeed the user needs to click on the text to extend/collapse itself and it is resulted not perfectly understandable.

Describe the solution you'd like
We suggest to add a more explicit button to use for extending/collapsing after the truncated text.
It should look similar to the following :

[atarix83]

@tdonohue

I'd add this topic as to discuss on the next community meeting, Do you agree?

[tdonohue]

@atarix83 : Sure, I'll add this to next week's meeting. I do agree that it may need usability improvements. We also should keep in mind that it was noted as having accessibility issues as well, see #1164

[atarix83]

this is just another option where the toggle has a different style

[ybnd]

The proposed fix would also address #1260