Add >note styles

[marin-bratanov]

At the moment, we appear to have styles only for >tip, >important and probably >caution. According to our style guide, >note is a separate type of alert box that has its own uses and should, ideally have its own styles: http://testdocs.telerik.com/style-guide/notes.

In the meantime, using the >tip styling for >note is a good workaround.

note This should be discussed with the design team so they can create proper styles according to the purpose of each type of alert box. At the moment the tip box is quite generic and does indeed look like it can be either a tip, or a note.

[imtodor]

From MS have different styles as well:
https://docs.microsoft.com/en-us/microsoftteams/teams-and-skypeforbusiness-coexistence-and-interoperability