Add notification queue

You can now stack as many notifications as you want and each will be displayed one after another.

Signed-off-by: Tom Diggle <tom@tomdiggle.com>
Change init method to return a instancetype property

Signed-off-by: Tom Diggle <tom@tomdiggle.com>
Minor code clean up

Signed-off-by: Tom Diggle <tom@tomdiggle.com>
Minor code clean up

Signed-off-by: Tom Diggle <tom@tomdiggle.com>
Add icon for message notification type

Signed-off-by: Tom Diggle <tom@tomdiggle.com>
Add icon for message notification type

Signed-off-by: Tom Diggle <tom@tomdiggle.com>
Change increased the size of the i

Signed-off-by: Tom Diggle <tom@tomdiggle.com>
Redesign error icon to match info icon

Signed-off-by: Tom Diggle <tom@tomdiggle.com>
Redesign the success icon to match info icon

Signed-off-by: Tom Diggle <tom@tomdiggle.com>
Change icons are no longer from ikonic set

Signed-off-by: Tom Diggle <tom@tomdiggle.com>