Add default template feature

[neocotic]

I've had this idea for a while and the concept is simple so I want to add it for the big release.

An additional option is assigned to each template option to indicate whether or not they are the default. 0 or 1 default template can exist at any time. If a default template exists then the popup doesn't display and the browser action instead triggers that template. This logic should also apply to the context menu, if enabled.

Also, when a default template exists a message should be displayed on the options page explaining what affect this has.

Finally, the keyboard shortcuts of all enabled templates should always be considered.

Optional

Additional options could be added to allow the user to display the icon and/or text in the browser action and context menu to either the default template or that of the extension. Obviously, these settings should only be considered when a default template exists.

[neocotic]

Added another option to be considered when the popup is being displayed. This option allows users to specify whether or not the popup should be hidden immediately after a template has been chosen.

Also, as part of #35, I've deprecated most of the options tags included in the initial change for this and added new ones (with better names). The following option tags now exist for this change;

• toolbarPopup
• toolbarPopupClose
• toolbarTemplate
• toolbarTemplateDetails
• toolbarTemplateName

[neocotic]

Along with the addition of the toolbarOptions tag (added in #62), the following tags have been changed;

• toolbarPopupClose renamed to toolbarClose
• toolbarTemplate removed (used invert of toolbarPopup instead)
• toolbarTemplateDetails renamed to toolbarStyle
• toolbarTemplateName renamed to toolbarKey (changed for Change way templates are uniquely identified #58)