Implement retrying in efd_win, fixes "Address in use" problem

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
Pavlo Kapyshin added to AUTHORS file.

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
Fix format specifier for uint64_t (fixes #205)
Fix warnings
adjustments to build on windows with mingw
Fix printing non-ascii chars in --quoted format for nanomsg
Remove unit64_t format specifier warnings

Explicitly cast to long long unsigned int to remove build warnings.
Fixed windows signalling bug (fixes #189)

Assuming that there may be a lag between nn_efd_signal and the data
available in nn_efd_unsignal, we set NN_SOCK_FLAG_IN/OUT if we have a
sucessful return from nn_efd_wait. Setting this flag is safe at any
time. And I expect that it should not create a bottleneck
Implement nn_symbol_info function

This is useful for two reasons:

* For language bindings to provide correct namespacing and type
  conversions of socket options
* To turn integer value into name (it's impossible without namespacing,
  because many symbols have same integer value)
Merge pull request #207 from borisz/bz/fix-warnings

Fix warnings for kqueue
Add Boris Zentner to AUTHORS
Merge pull request #216 from blutack/master

Remove uint64_t format specifier warnings
Add Gareth Roberts to AUTHORS
Merge branch 'master' of https://github.com/nanomsg/nanomsg
Tell build systems about utils/attr.h
Update ABI version numbers
Add release procedure documentation
Reset NN_VERSION_REVISION to 0, after all
Fix configure option name in RELEASING
Save useful commands in RELEASING