Remove ambertools to allow windows build

[synapticarbors]

Try to resolve #4 by removing what appears to be an unnecessary dependence on ambertools.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[synapticarbors]

@conda-forge-admin, please rerender

[synapticarbors]

@conda-forge-admin please rerender

[github-actions]

Hi! This is the friendly automated conda-forge-webservice.
I tried to rerender for you, but it looks like there was nothing to do.

[jchodera]

It looks like the win build is failing on the compilation of a cython extension we have since removed and replaced with numba:

   C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\VC\Tools\MSVC\14.16.27023\bin\HostX64\x64\link.exe /nologo /INCREMENTAL:NO /LTCG /DLL /MANIFEST:EMBED,ID=2 /MANIFESTUAC:NO /LIBPATH:D:\bld\openmmtools_1615515956881\_h_env\libs /LIBPATH:D:\bld\openmmtools_1615515956881\_h_env\PCbuild\amd64 "/LIBPATH:C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\VC\Tools\MSVC\14.16.27023\ATLMFC\lib\x64" "/LIBPATH:C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\VC\Tools\MSVC\14.16.27023\lib\x64" "/LIBPATH:C:\Program Files (x86)\Windows Kits\NETFXSDK\4.6.1\lib\um\x64" "/LIBPATH:C:\Program Files (x86)\Windows Kits\10\lib\10.0.17763.0\ucrt\x64" "/LIBPATH:C:\Program Files (x86)\Windows Kits\10\lib\10.0.17763.0\um\x64" /LIBPATH:D:\bld\openmmtools_1615515956881\_h_env\Library\lib /LIBPATH:D:\bld\openmmtools_1615515956881\_h_env\Library\lib /EXPORT:PyInit__mix_replicas build\temp.win-amd64-3.6\Release\./openmmtools/multistate/mixing/_mix_replicas.obj /OUT:build\lib.win-amd64-3.6\openmmtools\multistate\mixing\_mix_replicas.cp36-win_amd64.pyd /IMPLIB:build\temp.win-amd64-3.6\Release\./openmmtools/multistate/mixing\_mix_replicas.cp36-win_amd64.lib
       Creating library build\temp.win-amd64-3.6\Release\./openmmtools/multistate/mixing\_mix_replicas.cp36-win_amd64.lib and object build\temp.win-amd64-3.6\Release\./openmmtools/multistate/mixing\_mix_replicas.cp36-win_amd64.exp
    _mix_replicas.obj : error LNK2001: unresolved external symbol drand48
    build\lib.win-amd64-3.6\openmmtools\multistate\mixing\_mix_replicas.cp36-win_amd64.pyd : fatal error LNK1120: 1 unresolved externals
    error: command 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Enterprise\\VC\\Tools\\MSVC\\14.16.27023\\bin\\HostX64\\x64\\link.exe' failed with exit status 1120
    Running setup.py install for openmmtools: finished with status 'error'

We just need to cut a new openmmtools release.

@mikemhenry, can you help us cut the release for the recent updates to openmmtools, with @jaimergp giving you pointers?

We can then update this recipe for the latest release and hopefully get builds out.

[mikemhenry]

@jchodera Can do! I'll work with @jaimergp on the release, PR will be here:
choderalab/openmmtools#503

[jchodera]

@mikemhenry : Can you ascertain whether this is still relevant?

[mikemhenry]

Yes! I will:

• Check to see if unit tests pass if we remove ambertools
• Check to see if we can install openmmtools on a windows box