added TFTP to the list of supported protocols

glibc versions, and with this patch applied it no longer shows up to me. The
problem was indeed a flaw that made curl use a file handle already closed.

of the end of a chunked-encoded POST request.

Should we do this for all targets?

have this check done on far too many places by now...

added. TODO: add them to docs. add TFTP server to test suite. add TFTP to
list of protocols whereever those are mentioned.

broke krb4 builds!

quick hack to make it working again on Win32 - however we should consider to set some defaults depending on the compiler architecture we guess we are since it doesnt work well if we prefer building the msvc makefile with gmake instead of nmake because we found gmake first in path....

Kevin Lussier pointed this out!

for Windows, that could lead to an Access Violation when the multi interface
was used due to an issue with how the resolver thread was and was not
terminated.

about what each single lib may be used for.