Add rotate slice optimization.

Disabled until broadcast mapping is supported.
mv rpc from python to cython
mv cloudpickle from python to cython
add fast update (without slicing) for entire tile update
Make Broadcast support map over tiles.
Fixed the good_tile_shape bug.
Fixed bugs related to the good_tile_shape bug.
Merge pull request #89 from fegin/broadcast

Make Broadcast support map over tiles.
Merge pull request #88 from fegin/bugfixed

Fixed the good_tile_shape bug.
change serializationIOStream to serialization_buffer
add unordered_set.pxd
fix test_performance's baseline
Merge branch 'master' of github.com:spartan-array/spartan
Merge pull request #90 from spartan-array/rotate-slice-map

Rotate slice map
Merge pull request #87 from MaggieQi/master

change rpc to fast cython implementation
change condition to pthread_cond
Merge pull request #91 from MaggieQi/master

change condition to pthread_cond
prot node_type to traits
merge from cython
get rid of all the _members and some minor changes
Merge pull request #92 from EasonLiao/traits

Port from node_type to traits