Add modular library level build file. #27

Job	Run time
osx (ASAN=off LIBCXX=off CXXFLAGS='-DBOOST_HOF_HAS Job 0, boost, macos-10.15, clang++, 11.7, -DBO...	1s
posix (CLANG_VERSION=3.5 ASAN=on LIBCXX=on Job 1, boost, util-linux g++-4.9 clang-3.5 valgrind, u...	6m 51s
posix (CLANG_VERSION=3.5 ASAN=on LIBCXX=off Job 2, boost, util-linux g++-4.9 clang-3.5 valgrind, ...	4m 35s
posix (CLANG_VERSION=3.8 ASAN=off LIBCXX=on BUILD_EX Job 3, boost, util-linux g++-4.9 clang-3.8 v...	4m 57s
posix (CLANG_VERSION=3.8 ASAN=off LIBCXX=off BUILD_E Job 4, boost, util-linux g++-4.9 clang-3.8 v...	4m 46s
posix (CLANG_VERSION=3.8 ASAN=off LIBCXX=off CXX11=o Job 5, boost, util-linux g++-4.9 clang-3.8 v...	4m 54s
posix (GCC_VERSION=7 ASAN=off LIBCXX=off Job 6, boost, g++-7 valgrind, ubuntu-20.04, ubuntu:16.04...	4m 10s
posix (GCC_VERSION=6 ASAN=off LIBCXX=off Job 7, boost, g++-6 valgrind, ubuntu-20.04, ubuntu:14.04...	4m 38s
posix (GCC_VERSION=5 ASAN=off LIBCXX=off Job 8, boost, g++-5 valgrind, ubuntu-20.04, ubuntu:16.04...	3m 15s
posix (GCC_VERSION=4.9 ASAN=off LIBCXX=off Job 9, boost, g++-4.9 valgrind, ubuntu-20.04, ubuntu:1...	3m 38s
posix (GCC_VERSION=4.8 ASAN=off LIBCXX=off Job 10, boost, g++-4.8 valgrind, ubuntu-20.04, ubuntu:...	3m 34s
posix (GCC_VERSION=4.7 ASAN=off LIBCXX=off Job 11, boost, g++-4.7 valgrind, ubuntu-20.04, ubuntu:...	2m 46s
posix (GCC_VERSION=4.6 ASAN=off LIBCXX=off Job 12, boost, g++-4.6 valgrind, ubuntu-20.04, ubuntu:...	2m 54s
	50m 59s

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