M2d Prepare code for new design & add accessibility

[timea-solid]

This work will include updated to HTML5 styles and accessibility elements in the profile-pane.
At the same time CSS files will be consolidated locally and a CSS and theming strategy will be implemented.

[timea-solid]

See:

• profile-pane: With accessibility profile-pane#160
• solid-panes: Improving basic style solid-panes#433
• mashlib : New style mashlib#257