* add possibility to use native sendFile from OS for HttpServerResponse
add option POCO_USE_SENDFILE_FOR_HTTPSERVER, default - OFF
add test for HttpServer - testFile
add define fro Config.h POCO_USE_SENDFILE_FOR_HTTPSERVER
* my fail, be carefull with macro and brackets
* replace option POCO_USE_SENDFILE_FOR_HTTPSERVER with compiletime
detected macro POCO_HAVE_SENDFILE
replace types for sendFile with platform depended
wrap possibility of using sendFile with macro, if sendFile doesn't exist
in OS, then all methods don't exist
* remove option POCO_USE_SENDFILE_FOR_HTTPSERVER from ci.yml
* wrap testSendFile in the suite with define POCO_HAVE_SENDFILE
* try fix compile problem with emscripten
* oh, emscripten again
* fix logical error in testSendFile
* fix problem with cmake-specific macro when usinf make-project
* revert types from platform depended to Poco::Int64 and Poco::UInt64
for sendfile