windows: fix utf16->utf8 conversion in uv_fs_readdir
linux: fall back to traditional syscalls if necessary

libuv uses feature checks to determine if newer syscalls like pipe2() are
available. This works fine until someone compiles libuv against kernel headers
that are newer than the actual kernel our software runs on.

Fall back to traditional (but race-y!) syscalls when the kernel reports ENOSYS
or EINVAL.
windows: turn WSAECONNABORTED from WSARecv to UV_ECONNRESET
Alternative errno strategy
Shared uv_strerror
Remove unnecessary errno
Fix warning: comma at end of enumerator list
freebsd: remove unused variables
unix: remove unused uv__translate_lib_error() function
sunos: add getaddrinfo() compatibility hack

getaddrinfo() returns EAI_MEMORY if strlen(hostname) >= MAXHOSTNAMELEN
sunos: check that event ports supports fs watching
Use (void) for a function taking no arguments - fix gcc -Wstrict-prototypes
test: remove dead code
bench: fix compiler warnings
Fix typo that broke libuv on NetBSD: psysconf() -> sysconf()
Add support for DragonFly BSD by sharing code for FreeBSD.
Update AUTHORS and .mailmap
Bump version to v0.6
Set uv_write_t errno correctly

Fixes #206.
windows: return UV_FILE for non-console FILE_TYPE_CHAR