Add CPython 2.7.13 (#782)

https://www.python.org/downloads/release/python-2713/.

plugins/python-build/share/python-build/2.7.13

@@ -0,0 +1,8 @@
+#require_gcc
+install_package "openssl-1.0.2g" "https://www.openssl.org/source/openssl-1.0.2g.tar.gz#b784b1b3907ce39abf4098702dade6365522a253ad1552e267a9a0e89594aa33" mac_openssl --if has_broken_mac_openssl
+install_package "readline-6.3" "https://ftpmirror.gnu.org/readline/readline-6.3.tar.gz#56ba6071b9462f980c5a72ab0023893b65ba6debb4eeb475d7a563dc65cafd43" standard --if has_broken_mac_readline
+if has_tar_xz_support; then
+  install_package "Python-2.7.13" "https://www.python.org/ftp/python/2.7.13/Python-2.7.13.tar.xz#35d543986882f78261f97787fd3e06274bfa6df29fac9b4a94f73930ff98f731" ldflags_dirs standard verify_py27 ensurepip
+else
+  install_package "Python-2.7.13" "https://www.python.org/ftp/python/2.7.13/Python-2.7.13.tgz#a4f05a0720ce0fd92626f0278b6b433eee9a6173ddf2bced7957dfb599a5ece1" ldflags_dirs standard verify_py27 ensurepip
+fi