scikit-hep/boost-histogram: Version 0.6.0

This version fills out most of the remaining features missing from the 0.5.x series. You can now use all the storages without the original caveats; even the accumulators can be accessed array-at-a-time without copy, pickled quickly, and set array-at-a-time, as well.

The API has changed considerably, providing a more consistent experience in Python. Most of the classic API still works in this release, but will issue a warning and will be removed from the next release. Please use this release to transition existing 0.5.x code to the new API.

• Histogram and Axis classes now follow PEP 8 naming scheme (histogram->Histogram, regular->Regular, int->Int64 etc.) #192, #255
• You can now view a histogram with accumulators, with property access such as h.view().value #194
• Circular variable and integer axes added #231
• Split Category into StrCategory and IntCategory, now allows empty categories when growth=True #221
• StrCategory fills are safer and faster #239, #244
• Added axes transforms #192
• Function(forward, inverse) transform added, allowing ultra-fast C function pointer transforms #231
• You can now set histogram contents directly #250
• You can now sum over a range with endpoints #185
• h.axes now has the functions from axis as well. #183
• bh.project has become bh.sum #185
• .reduce(...) and the reducers in bh.algorithm have been removed in favor of dictionary based UHI slicing #259
• bh.numpy module interface updates, histogram=bh.Histogram replaces cryptic bh=True, and density=True is now supported in Numpy mode #256
• Added hist.copy() #218 and hist.shape #264
• Signatures are much nicer in Python 3 #188
• Reprs are better, various properties like __module__ are now set correctly #200

• Unlimited and AtomicInt storages now allow single item access #194
• .view() now no longer makes a copy #194
• Fixes related to string category axis fills #233, #230
• Axes are no longer copies, support setting metadata #238, #246
• Pickling accumulator storages is now comparable in performance simple storages #258

• The linux wheels are now 10-20x smaller #229
• The hist/axis classes are now pure Python, with a C++ object inside #183
• Most internal names changed, core->_core, etc. #183
• The uhi module is now tag. #183
• boost_histogram.cpp as bh provides C++ high-compatibility mode. #183
• Indexing tags now use full UHI instead of workarounds #185
• Removed log and sqrt special axes types#231
• Family and registration added, new casting system #200