[boost] [tokenmap] updated perfect hash container in sandbox

Subject: [boost] [tokenmap] updated perfect hash container in sandbox
From: Slawomir Lisznianski (sl_at_[hidden])
Date: 2010-04-21 10:04:51

Changes:

* To eliminate a possibility of the algo for finding free slots becoming 
slower as the load factor increases, the container now keeps track of 
open slots in unused nodes. This guarantees constant time insertion of 
new elements at a slight bookkeeping overhead. Consequently, the 
load-factor has been removed. Pointed by Daniel James.

* More STL compliant (iterators, size(), empty(), etc)