ENH: special._testutils: add option for accepting nans by default in tests
ENH: special/_testutils: make FuncData accept a comparison functions rather than only taking numerical data
TST: special: add systematic tests against mpmath

This systematically cross-checks values from (nearly) all special
functions that exist both in mpmath and scipy.
ENH: special/_testutils: add an option for ignoring the sign of infinity
TST: special: work around limiting value issues in lpmv & hyp2f1 tests
Merge pull request #500 from pv/special-mpmath-syst-submit

TST: special: test against (nearly) everything in mpmath
Correctly interpret logical matlab arrays as booleans when mat_dtype is set
TST: stats: add another test for find_repeats()
MAINT: stats: simplify (and speed up a bit) some code in wilcoxon()
TST: special/test_mpmath: fix elliptic function tests
BUG: memory leak fix in convolve2d.
Merge pull request #508 from gustavla/master

BUG: signal: memory leak in convolve2d
MAINT: cluster: Remove unused imports, unused variables and commented-out code from hierarchy.py
Merge pull request #510 from WarrenWeckesser/cluster-cleanup

MAINT: cluster: Remove unused imports, unused variables and commented-out code from hierarchy.py
DOC: io: update code comment and whosmat docstring
Merge pull request #504 from batterseapower/master

ENH: io: Present loaded logical Matlab arrays with a boolean dtype

There was already some code which attempted to do this in the Matlab
file reader, but it was broken. To be specific, the old code assigned to
a dtype to a local variable bool_dtype rather than self.bool_dtype, and
so later attempted uses of that dtype would be null/None and so would
not have an effect.

This change makes also the writer set the logical flag if you write out
an array of bools.
BUG: special: add a missing term in the asymptotic expansion of Fresnel C/S
Merge pull request #501 from pv/special-fresnel

BUG: special: add a missing term in the asymptotic expansion of Fresnel C/S
BUG: special: switch to AMOS implementation of Airy functions at large arguments

The Cephes implementation gives wrong results (relative tolerance >
1e-12) after |x| > 10.
GEN: special: regenerate files