Make benchmarks run again

DataStream benchmarks disabled, since they don't work and the
corresponding tests are also disabled
track Julia change (moving TimSort to SortingAlgorithms.jl)
Merge pull request #361 from tanmaykm/tanmaykm

track Julia change (moving TimSort to SortingAlgorithms.jl)
Revised DataStreams
Fix similar
Clean up unary operators
Clean up matrix multiplication

May need additional tests
Only define the necessary similar operator, and make it accept types
Clean up comparison operators
Clean up arithmetic operators
Clean up most remaining operators, and restore operator lists for now
Remove cov_spearman and colffts from tests
Move all macros to top
Make operator arrays const
Fix ambiguity warnings