Implement some skin examples for BASE

[Nicklas Nordborg]

See ​http://base.thep.lu.se/ticket/1886 and ​http://base.thep.lu.se/ticket/1890

Some ideas:

• A skin with a different color scheme than gray.
• A "Test server" skin that makes it easy to see if you are on the "test server" or the "production server".

[Nicklas Nordborg]

(In [2932]) References #696: Implement some skin examples for BASE

Initial checkin with project files and single very simple extension

[Nicklas Nordborg]

(In [2967]) References #696: Implement some skin examples for BASE

Added "Gold" skin. It has a fully commented CSS file and should be a good starting point for anyone wanting to create a new skin.

[Nicklas Nordborg]

(In [2968]) References #696: Implement some skin examples for BASE

Added "Server ID" skin which adds a small notice with the server hostname + url in the menu bar.

The "Test server" skin was updated to make the server id notice a bit more visible.

[Nicklas Nordborg]

(In [2969]) References #696: Implement some skin examples for BASE

Added customizations for selected items, menu sections and notifications.

[Nicklas Nordborg]

(In [2971]) References #696: Implement some skin examples for BASE

Need more specificty on h1 selector.

[Nicklas Nordborg]

(In [2972]) References #696: Implement some skin examples for BASE

Added color for progress bar.

[Nicklas Nordborg]

(In [2975]) References #696: Implement some skin examples for BASE

Changed background color in notes.

[Nicklas Nordborg]

(In [2977]) References #696: Implement some skin examples for BASE

Updated README.

[Nicklas Nordborg]

(In [2978]) References #696: Implement some skin examples for BASE

Adding a configuration dialog that can be used to set the text in the "Server ID" notification.

[Nicklas Nordborg]

(In [2982]) References #696: Implement some skin examples for BASE

A little bit smaller text notice.