more improvements

*added execution_time
*changed experiments to optimise on mean and added 4 single+gauss ones
* removed use_cosinecache
* remade contig_static from ground up, read comments in
get_contigstatic2. Now modifies cosine matrix in place with past/future
traces and 2 diff maps for contig penalization, added new parameter for
that and removed the contig window size parameter
* cost matrices now scale themselves inside and dont run if the usage
param is 0
* there was an error in my implementation of get_costsum3 so its gone
and we revert to the method used in paper, contig_static now uses that
* run times are added to results and aggregate results
* pack memory between experiments
* now a vis() method on show
* memory_efficient param uses so on the big experiment we dump cosine
and cost matrices to save memory