Revert "_HTTPConnection: check location on _should_follow_redirect() and retain safe request when following redirects (#2409)"
Revert "_HTTPConnection: check location on _should_follow_redirect() and retain safe request when following redirects (#2409)"

This reverts commit 859a038eb9c1af99d3871c9972f0826a1d05475d.

This commit was merged after the release of 5.1b1 with insufficient
consideration and testing. I'll bring this back in the 6.0 cycle with
a test

dongpinglai/my_tornado,NoyaInRain/tornado,NoyaInRain/tornado,mivade/tornado,lilydjwg/tornado,tornadoweb/tornado,tornadoweb/tornado,dongpinglai/my_tornado,bdarnell/tornado,hhru/tornado,NoyaInRain/tornado,wujuguang/tornado,lilydjwg/tornado,dongpinglai/my_tornado,allenl203/tornado,bdarnell/tornado,hhru/tornado,bdarnell/tornado,allenl203/tornado,dongpinglai/my_tornado,hhru/tornado,mivade/tornado,mivade/tornado,dongpinglai/my_tornado,mivade/tornado,hhru/tornado,NoyaInRain/tornado,wujuguang/tornado,bdarnell/tornado,allenl203/tornado,lilydjwg/tornado,allenl203/tornado,tornadoweb/tornado,dongpinglai/my_tornado,lilydjwg/tornado,mivade/tornado,allenl203/tornado,wujuguang/tornado,hhru/tornado,NoyaInRain/tornado,bdarnell/tornado,NoyaInRain/tornado,wujuguang/tornado,tornadoweb/tornado,wujuguang/tornado