* Add several fixes for python toolchain
* Fix versin regex
* Make script exit on error
* Fix version regex
* Fix version regex
* Fix version regex
* Fix version regex
* Make test run on the current commit
* Fix test
* Fix test
* Use git to retrieve current commit
* Fix tests
* Fix tests
* Also make linux and mac work on the current commit
* Fix test
* Use gnu for ruby build because strptime is provided by posix
* Move option to extconf.rb
* Remove unused code in Rakefile
* Add config files for kokoro test
* Use gnu 11
* Define _XOPEN_SOURCE
* Add gnu11 option
* Remove XOPEN
* Try base_cc_flags
* Try config_options
* Move time.h to top
* Try -D_XOPEN_SOURCE=700
* Define XOPEN_SOURCE directly
* Try extconf.rb
* Try CFLAGS
* Try ext.cross_config_options
* Make mac ruby release job fail on error
* Try again
* Try define _XOPEN_SOURCE in extconf.rb
* Try again
* Define __USE_XOPEN
* Remove 2.6.0
* No mingw
* Throw error on mingw
* Remove XOPEN_SOURCE in upb
* Add back mingw
* Remove comment
* Fix python release build.
* Separate config.sh by platform
* Use KOKORO_JOR_NAME to determine the BUILD_COMMIT.
* Use -std=c++14 on MacOS so -latomic can be used.
* Add kokoro build for python source package
* Use libc++ for xcode 10 (#5303)
The xcode 10 removes the deprecated libstdc++ library. We could set
"MACOSX_DEPLOYMENT_TARGET" to "10.9" to use libc++ instead.
* Add python 3.7 build
* Add build for python 3.7 on linux and windows
* Remove unused source build
* Add comment
* Fix $MACOSX_DEPLOYMENT_TARGET mismatch
* Fix MACOSX_DEPLOYMENT_TARGET mismatch
* Add missing import for sysconfig
* Add missing imports
