StuffKeeper, speedups

By moving some code around, I been able to speedup the startup a factor 3 (0.3 seconds now from startup to gtk_main()).This by first loading the backend, then hooking it into the  interface. This saves a whole lot of signals and updates.

More speedups by changing the treeview to fixed-height mode, this speedsup a forced reload by a factor 4 (around 0.2 seconds).

Please give it a try, and see how fast it start (it print out some stats on the console).

p.s. I also changed the template parsing  in html export.  For boolean items, you can now specify what to print out when the value is TRUE or FALSE, instead of printing out the text True  or False.

(example see http://random.sarine.nl/laptop.html  )