Add CPython 3.7.6 (#1498)

plugins/python-build/share/python-build/3.7.6

@@ -0,0 +1,10 @@
+#require_gcc
+prefer_openssl11
+export PYTHON_BUILD_CONFIGURE_WITH_OPENSSL=1
+install_package "openssl-1.1.0j" "https://www.openssl.org/source/openssl-1.1.0j.tar.gz#31bec6c203ce1a8e93d5994f4ed304c63ccf07676118b6634edded12ad1b3246" mac_openssl --if has_broken_mac_openssl
+install_package "readline-8.0" "https://ftpmirror.gnu.org/readline/readline-8.0.tar.gz#e339f51971478d369f8a053a330a190781acb9864cf4c541060f12078948e461" mac_readline --if has_broken_mac_readline
+if has_tar_xz_support; then
+  install_package "Python-3.7.6" "https://www.python.org/ftp/python/3.7.6/Python-3.7.6.tar.xz#55a2cce72049f0794e9a11a84862e9039af9183603b78bc60d89539f82cf533f" ldflags_dirs standard verify_py37 copy_python_gdb ensurepip
+else
+  install_package "Python-3.7.6" "https://www.python.org/ftp/python/3.7.6/Python-3.7.6.tgz#aeee681c235ad336af116f08ab6563361a0c81c537072c1b309d6e4050aa2114" ldflags_dirs standard verify_py37 copy_python_gdb ensurepip
+fi