AMBER 20 easybuild script with gpsmkl and NCCL

We use system SciPy-Stack rather than letting AMBER download its
own. We use NVidia NCCL library for inter-GPU communications.
We also use system MKL and Boost.  This was tested on JUWELS-BOOSTER.

Golden_Repo/a/AMBER/AMBER-20-gpsmkl-2020.eb

+easyblock = 'CMakeMake'
+
+name = 'AMBER'
+version = '20'
+
+homepage = 'http://ambermd.org'
+description = """
+AMBER: 'Assisted Model Building with Energy Refinement' is a set of molecular
+mechanics force fields and a package of molecular simulation programs.
+
+Citation:
+D.A. Case, K. Belfon, I.Y. Ben-Shalom, S.R. Brozell, D.S. Cerutti,
+T.E. Cheatham, III, V.W.D. Cruzeiro, T.A. Darden, R.E. Duke, G. Giambasu,
+M.K. Gilson, H. Gohlke, A.W. Goetz, R. Harris, S. Izadi, S.A. Izmailov,
+K. Kasavajhala, A. Kovalenko, R. Krasny, T. Kurtzman, T.S. Lee, S. LeGrand,
+P. Li, C. Lin, J. Liu, T. Luchko, R. Luo, V. Man, K.M. Merz, Y. Miao,
+O. Mikhailovskii, G. Monard, H. Nguyen, A. Onufriev, F.Pan, S. Pantano,
+R. Qi, D.R. Roe, A. Roitberg, C. Sagui, S. Schott-Verdugo, J. Shen,
+C. Simmerling, N.R.Skrynnikov, J. Smith, J. Swails, R.C. Walker, J. Wang,
+L. Wilson, R.M. Wolf, X. Wu, Y. Xiong, Y. Xue, D.M. York
+and P.A. Kollman (2020),
+AMBER 2020, University of California, San Francisco.
+"""
+
+site_contacts = 'Sandipan Mohanty <s.mohanty@fz-juelich.de>'
+
+toolchain = {'name': 'gpsmkl', 'version': '2020'}
+toolchainopts = {'pic': True}
+
+builddependencies = [
+    ('CMake', '3.18.0'),
+    ('binutils', '2.34',),
+]
+dependencies = [
+#    ('CMake', '3.18.0'),
+    ('FFTW', '3.3.8'),
+    ('Python', '3.8.5'),
+    ('SciPy-Stack', '2020', '-Python-%(pyver)s', ('gcccoremkl', '9.3.0-2020.2.254')),
+    ('Boost', '1.74.0','-nompi'),
+    ('flex', '2.6.3'),
+    ('NCCL','2.8.3-1','-CUDA-11.0'),
+]
+# Something in the source is causing flex 2.6.4 to SEGFAULT. Keep it at 2.6.3
+# until it is fixed. /SM 2021-05-13
+
+sources = [
+    'AmberTools20.tar.bz2',
+    'Amber20.tar.bz2',
+]
+
+separate_build_dir = True
+local_build_mpi_parts = "TRUE"
+local_build_cuda_parts = "TRUE"
+local_build_cuda_nccl = "TRUE"
+
+preconfigopts = "CC=gcc && CXX=g++ && COMPILER=GNU "
+preconfigopts += " && cd %(builddir)s/amber20_src && "
+preconfigopts += " ./update_amber --update && cd ../easybuild_obj && "
+
+configopts = "-DCOMPILER=GNU -DCHECK_UPDATES=OFF -DAPPLY_UPDATES=OFF -DBUILD_GUI=FALSE "
+configopts += " -DINSTALL_TESTS=TRUE  -DMPI=%s " % local_build_mpi_parts
+configopts += " -DDOWNLOAD_MINICONDA=FALSE -DTRUST_SYSTEM_LIBS=TRUE "
+configopts += " -DCUDA=%s " % local_build_cuda_parts
+configopts += " -DNCCL=%s " % local_build_cuda_nccl
+buildopts = 'NVCC_GENCODE="-gencode=arch=compute_70,code=sm_70 \
+                           -gencode=arch=compute_75,code=sm_75 \
+                           -gencode=arch=compute_80,code=sm_80"'
+
+modextravars = {
+    'AMBERHOME': '%(installdir)s/',
+}
+
+modluafooter = '''
+add_property("arch","gpu")
+'''
+
+group = "amber"
+
+modloadmsg = '''
+The access to this software is restricted to members of the group "amber".
+The JSC has a site licence for academic users. If you would like to get
+access please see:
+"http://www.fz-juelich.de/ias/jsc/EN/Expertise/Support/Software/Chemistry/AmberConfirmationOfLicence.html"
+'''
+
+moduleclass = 'bio'
+
+