Start cleaning up the Win32 code. This cleans up the code which spawns

child processes. The changes are

 -- remove an unbounded sprintf()
 -- always check for errors at all stages, and log an error message
 -- if an error occurs in creating a child, die, but make sure
    all already created children a killed correctly
 -- remove assert()'s


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@81219 13f79535-47bb-0310-9956-ffa450edef68