changed PCA to truncated SVD
Testing log_loss and hinge_loss under THRESHOLDED_METRICS
FIX: Removed redundant code
TST: Test class variance and string input
FIX: Changed str vs float invariance test
Merge pull request #2717 from Manoj-Kumar-S/test_log_loss

Testing log_loss and hinge_loss under THRESHOLDED_METRICS
Add learning curve
MISC remove accidentally commited file. Whoops!
DOC add learning_curve to what's new and API reference

+ PEP8 fixes

+ Alphabetical ordering fix for classes.rst

+ Example reference
FIX explicit type for offset variable
Handle n_features < n_informative case in make_regression.

Useful if n_informative is not explicitly specified, in which case
n_informative=10.
Regenerate C files
Wrong format specifier used when formatting exception message.
Python 3 compat
Python 3 fixes in exercises
Python 3 fixes for the second exercise
COSMIT get rid of deprecation warning in tree tests
MAINT deprecate HMMs

Fixes #2731.
MAINT ignore sklearn/tree/_utils.c in diff
COSMIT tree: unused variable warnings and use for/range

Not recompiled with Cython, as line numbers still match up.