Modernize the codebase - convert C-style casts to static_casts #3794

Job	Run time
black	33s
clang-format	17s
cppcheck	6m 41s
copyright_headers	16s
flake8	24s
forbidden_types	20s
mypy	33s
lychee_IGNORED	22s
pydocstyle	22s
pylint	51s
rstcheck	18s
unused_names	16s
vale	34s
sphinx-rtd	3m 4s
sphinx-conda	0s
build_macos (macos-latest, clang, openmp, mpi, python, gsl, ltdl, boost, hdf5, optimize, warning)	26m 44s
build_linux (ubuntu-20.04, gcc, boost, optimize, warning)	16m 38s
build_linux (ubuntu-20.04, gcc, openmp, python, gsl, ltdl, boost, optimize, warning)	24m 31s
build_linux (ubuntu-20.04, gcc, mpi, python, gsl, ltdl, boost, optimize, warning)	25m 9s
build_linux (ubuntu-20.04, gcc, openmp, mpi, python, gsl, ltdl, boost, hdf5, sionlib, libneurosim...	32m 44s
	2h 20m 37s

Provide feedback