Different design for action buttons and folder buttons

[klues]

Currently all buttons have the same design. This sometimes can be confusing, e.g. it is maybe not clear on first sight if the user is on the "add page", where he/she can select a new device to add or on the "control page" where he/she sees the already configured devices to control.

so the idea is:

• action buttons should have an own design (other color?!). it would also be nice to somehow show the status of a sent command. it should be visible for the user if a command was sent successfully or not (e.g. if IrTrans is not connected). I do not know if this indicator should be inside of the button or if we should show a error message on the top of the page if sending of a command failed (+ link to installation/error handling wizard)
• folder buttons should have an own design.

So in the end it should be clear for the user if a button (a) directly sends an action, (b) brings the user to a subfolder of a learned command or (c) brings the user to a subpage like help/install wizard, etc.

[klues]

partly done with #87

not done:
show status of sending command in button