remove files that were part of the origal repo
rework randomgen docs to integrate with numpy and fix some links
remove convenience functions, require explicit call to gen.brng
move code out of numpy.random.randomgen into numpy.random

first cut at building randomgen
upgrade 'cythonize' and fix absolute imports to relative
define NPY_NO_DEPRECATED_API and fix other warnings
enable pgc64 by always using PCG_EMULATED_MATH
refactor so import randomgen works
add TODO comments for pcg64 improvements
fix imports, module name in setup.py; remove _testing
make cythonize non-recursive, restore examples to proper place
update to randomgen 7bca296c0b9
replace mtrand with LegacyGenerator, tweak for compatibility
port f879ef4 to fix GH10839
minimized difference between generator.pyx and _legacy.pyx
fix namespace in doctests, mark results that are random
update to randomgen commit 95c8cdd1c
Incorporate testing of edge cases into main tests
Rename test files to describe their purpose
Import import locations to reflect numpy paths
Correct tolerance on float32 tests
Remove set_printoptions
Remove complex normal
Remove future imports
Pull in BasicRNG source changes from original author
Small doc fixes
_mtrand => _rand
Improve consistency of nan handling
Prevent nans prducing values from int functions
add randomgen documentation to the tree

Finally seems to make the GitHub license detection mechanism happy

Reason: the GitHub license detection method relies on the LICENSE
file matching for at least 95% with a standard license.
Adding even one more sentence changes the license displayed in the
GitHub UI and also in the GitHub API that can be queried from
BSD to "other".

See https://github.com/numpy/numpy/issues/13447 for more
details.

Note that this split license is what GitHub recommends to do,
and is also what we do for wheels, where we append to the license
file at build time.