[henshin-dev] Profiling support and match finder optimizations

[Christian Krause <henshin.ck@xxxxxxxxx>]

Hi,

I added an application monitor implementation that measures the time 
need to execute rules and that generates some statistics. This is very 
nice for profiling transformations.

I used it already for profiling a transformation of one of our Master 
students. Based on his example, I was able to add a tweak to the match 
finder which in certain scenarios increases the performance by an order 
of magnitude. Basically, I sort the nodes in a LHS (technically the 
variables in the match finder) based on the size of their domains, such 
that the nodes with the smallest domains are matched first. As I said, 
this can make a huge difference in the performance.

Cheers,
Christian