As part of the PR, it also fixes:
 - Removes button aliases
 - Unifies the keys in the object returned by getAllToolboxButtons and the button keys
 - Makes sure that the number of buttons displayed are always the same as the number of buttons specified in the thresholds and removes the exception for not filling up the main toolbar with buttons from overflow menu when reactions button is disabled.
 - Introduces a priority for buttons that will be used to fill empty spaces in the main toolbar.

Fixes the issue with adding duplicate elements in buttonsWithNotifyClick and participantMenuButtonsWithNotifyClick with custom buttons.

Filters the toolbarButtons in redux depending on the visitor state instead of filtering them every time in mapStateToProps. This will prevent unnecessary rerenders of the toolbar.

Additionally:
 - Moves visitor buttons const from features/config in features/toolbox.
 - Removes dublicate functions isButtonEnabled and isToolbarButtonEnabled.
 - Adds more buttons to the visitor allowed buttons which functionality has been any way accessible trough shortcuts or somewhere else.
 - Enables customButtons to be visible for visitors.

The previous version of getToolbarButtons function was actually adding the custom buttons on every call to the config toolbarButtons array, effectively creating dublicates of every custom button. The PR fixes this issue.

Also now we will be running the getToolbarButtons calculation only when needed.

* Convert all vh units to dvh; fixing layout for mobile browsers such as Chrome for Android.

allows chat button to be displayed when there should be enough space for it

- add possibility to allow execution of the button's routine besides triggering
`toolbarButtonClicked` API event
- keep backwards compatibility
- get rid of `ToolbarButton`

Move some styles from SCSS to JSS

- deprecate `INITIAL_TOOLBAR_TIMEOUT`, `TOOLBAR_ALWAYS_VISIBLE`, `TOOLBAR_TIMEOUT`

* feat(toolbox) allow any toolbox button to be displayed as main

fixes the previous behaviour where only a certain set of buttons were whitelisted for being displayed in the main toolbar

* code review

* code review - fix avatar icon position

The feature was not ported to the new toolbar. Arguable these
can all be moved into notification but for now simply the
logic will be removed and worked on again as demand arised.

* ref(info): be able to open dialog through store

* feat(info): automatically show the info dialog

Conditions:
- Lonely call
- Has not opened the info dialog yet

* squash: change to show on start, hide later

* squash: update naming and comment