Added cone H-bond criterion
Consolidated functions, periodic=True by default
Removed a function name that was causing a crash
Restored the constants into the function
Robert's suggested changes
Fixed docstring and angle_triplet2
Renamed wernet_nilsson function
actual content
bug with zero-sized arrays
use opt=False in the reference implemenetations
Merge pull request #1 from rmcgibbo/tests-for-484

additions to PR
Merge pull request #483 from leeping/hbond

Added cone H-bond criterion
Merge pull request #485 from rmcgibbo/opt=False

use opt=False in the reference implementations
Fix index error
Merge pull request #484 from rmcgibbo/zeros-sized-arrays

[MRG] Bug with zero-sized arrays
CHanges required to compile on windows
force upload
Merge pull request #487 from rmcgibbo/force-upload

force upload
toggle appveyor build
Merge pull request #486 from rmcgibbo/windows-fixes

VS2008 (Windows) Fixes