new raxml version

Alexis fixed a small bug in RAxML that only appeared on MacOSX.
updated manual
new tests for clustering algorithm

right now, many of these will fail. When they all pass, we can
release...
fixed minor bug in AIC and BIC calculation

which would only have arisen in the very rare circumstance that users
had terribly small data blocks. It would have been very unlikely to
make any real difference.
changed the name of some options

cluster-weights is now --weights

cluster-percent is now --rcluster-percent
updated manual
changed search names of clustering algorithms

now we have:

rcluster - relaxed clustering
hcluster - strict hierarchical clustering
updated manual again

one day I'll change this to .md format so we can actually see what
these updates are.
edited search names in christof's tests
fixed example .cfg file
nicer output
Fix wrong variable name
Slightly more robust weights handling
Bug in main -- cfg.reset can't be seen from scope
Initial clustering tests (almost working)
Ignore cruft from py.test
changed default weights to "1,0,0,0"
catch potential errors in 'weights' argument

and separate things out much nicer...
checks on rcluster-percent (== cluster_percent) variable

that it is >=0.0 and <=100.0
better user info on weights