Merge pull request #2499 from matthew-brett/better-error-too-small-mat4

ENH: io.matlab: More helpful error reading bad mat4 file
MAINT: move gcutils as a private module under scipy.lib

Also rename check_refs_for -> assert_deallocated
Merge pull request #2502 from matthew-brett/ref-counting-and-interp1d

ENH: interpolate: avoid reference cycles in interp1d
BUG: linalg: fix absolute imports in deprecated fblas/flapack/cblas/clapack modules

Closes gh-2490
BLAS level3 : syrk, syr2k
Merge pull request #2458 from pv/convexhull-vertices

ENH: spatial: Direct access to convex hull vertices
BLAS level 3: hemm, herk, her2k
MAINT: for logm(expm()) test only non-low precision
MAINT: style changes, an extra test, undo a previous change to TestHilbert
Merge pull request #2500 from argriffing/gh-2496

BUG: fix issue with rtype parameter to signal.unique_roots. Closes gh-2496
DOC: fix some issues in signal docstrings.

- remove "default" from ricker docstring
- add plt.figure() to example
- add more math tags, elaborate on Hilbert transform

Reviewed as https://github.com/scipy/scipy/pull/2455
Merge pull request #2494 from argriffing/rvs-faddeeva

BUG: fix non-symmetry in tails of stats.truncnorm distribution.
MAINT: some cleanups in stats.distributions tests.
BF: ensure ordering of OrderedDict keys

Test was failing because of unexpected key ordering - closes gh-2503.
MAINT: stats: remove unused '**kwds' from the definition of kstest()
MAINT: remove the file 'TEST_COMMIT'
Merge pull request #2506 from WarrenWeckesser/maint-rm-test-commit

MAINT: remove the file 'TEST_COMMIT'
Merge pull request #2505 from matthew-brett/mat-dict-py33-fixes

BF: ensure ordering of OrderedDict keys
ENH: allow nc <=0 in non-central t-distribution.  Closes issue gh-2402.

For the non-centrality parameter nc negative values and zero should be allowed.
Therefore an _argcheck added which only restricts degrees of freedom df to
positive values.
TST: add test for broadcasting in stats.nct distribution.