pecl_http docs

Hi docs folks, I have removed the documentation for the pecl_http extension from the English branch upon the maintainer's request. Our manual only documented v1, which caused lots of confusion given that the v2 (and now v3) API is very different. Good API documentation of the current versions of the extension is maintained by the extension author on his site [1], which is easier for him to maintain since it uses Markdown and he has an aversion to DocBook! In due course, I will go through the translations and tidy up. Regards, Peter P.S. If there is any strong dissent, please make yourselves known. [1] https://mdref.m6w6.name/http