Fixed markdown, added docu, added resource for uptime

[tnsasse]

Hi Adam, I would propose the following changes, feel free to integrate or reject them...

• I fixed the markdown formatting and listed the available resources.
• A handy uptime resource that (obviously) states the uptime in milliseconds since the app start. This can be used to calculate the average uptime in external tools easily, without having to deal with date calculations (and possibly time zones).

Downside: the WAR size is now 12 kB instead of only 9kB ;-)