pywsgi: make write() and start_response() methods, not closures; remove minimum_chunk_size; remove env['gevent.input'], use self.wsgi_input

--HG--
extra : transplant_source : b%0D%F9%87%CB%0DjA%D1%B5%D8%13b%3E%FA%DC%FC%14%F1%8D

--HG--
extra : transplant_source : ZA%1B%88%3E%BB%C8%D5%15S%BC%BC%5B%25%F0%D2%1C/%F3m

--HG--
extra : transplant_source : %F3%93%87q%87a%18Z7%09%F3%87%3C1%25%60%D3%EB%11o

--HG--
extra : transplant_source : %E0%A5%14%D7%21d%B8%CD1v6%91I%FE%27%E5a%A3%CE%C3

--HG--
extra : transplant_source : t%1C%DA%A7%B3%C3KZ%C9%0F%2C%82%08%93%D4%8Bi%9DWK

--HG--
extra : transplant_source : s%FF%AD%1AeG%2B-sGr%C7%2A%22D%B6%90u%87%F4

--HG--
extra : transplant_source : %80g7%B3e%22%B9%8F%C3%B5%E1%04%FBNq%E3%B1%C1%13%DE

--HG--
extra : transplant_source : .c%A2%C4%AD8w%207%85%C5%98%EC%95K%EDN%A3W%A1

--HG--
extra : transplant_source : %D3%23%3F%1ET%96%24%89%D7%D4z%C4%A9%BBv%7Ct%01%AB%2A

--HG--
extra : transplant_source : %A1%04%9Fa%98Xy%ABR%B4%B4Zg%E4%60%3E%92%1A%81%D6

- the latter can even call 'uname' which is not necessary in this case.