Fix typo in comment

Include URI parameter in example client help

It is better to process data if client has 1RTT key without buffering
them.  This is primarily for response against 0RTT request, but it
also handles the .5RTT CRYPTO data which might include
NewSessionTicket.

@NKTelnet identified this bug and proposed the initial patch which
fixes it differently.  See #143

because ISO C requires that enum value must be of type int.

Currently, when configuring with --disable-shared the following error is
generated when running make check:
make[2]: *** No rule to make target `../lib/.libs/*.o',
needed by `main'.  Stop.
make[2]: *** Waiting for unfinished jobs....

This commit adds a conditional for this case.

extend callback is only called when server sends MAX_STREAMS frame.
The initial limit must be set explicitly.

Add struct tags for structs used in callbacks.

This allows them to be forward declared. Typedefed anonymous structs
cannot be forward declared without a tag.