Added tee_i_stream_child_is_waiting(). --HG-- branch : HEAD

Changed .h ifdef/defines to use <NAME>_H format. --HG-- branch : HEAD

Removed memory pool parameter from iostreams. Default pool was almost always used, and the stream usually required destroying anyway so it didn't even make freeing memory easier. --HG-- branch : HEAD

Added tee-istream, which can be used to create multiple readable input streams from one input stream. --HG-- branch : HEAD