add cholesky matrix decomposition
Merge branch 'master' of github.com:spartan-array/spartan

Conflicts:
	spartan/examples/cholesky.py
	spartan/expr/region_map.py
	tests/test_cholesky.py
change pthread_cond_wait to pthread_cond_timedwait to allow CTRL-C
update the test_cholesky
Merge branch 'master' of github.com:spartan-array/spartan
Merge branch 'master' of github.com:MaggieQi/spartan
add lda application
Bug fixed and performance improvement
Bug fixed
Bug fixed
A missing file
fix a typo in builtin.py. from norm_mapper to _norm_mapper
naming
Merge pull request #104 from fegin/develop

Bug fixed and performance improvement
Add retile operation.

This keeps the same arrat shape but changes the underlying tiling.
Merge pull request #105 from MaggieQi/master

Add LDA topic model to example
Merge pull request #106 from spartan-array/add-retile-operation

Add retile operation.
fixed the spartan.array dot product with vector bug.
deprecate logging in dot mapper
fix the bug in a better way.
init np.random.seed in every worker.
rephrase the comment