Add :fd to tcp-server for listening on an exising file descriptor.
Merge pull request #102 from fukamachi/tcp-server-on-fd

Allow tcp-server to listen on an exising file descriptor
merge in uv branch, choosing uv tcp-server fd stuff over libeven (obvis)
Remove remaining mentions of libevent.
catch-app-errors: no need to use (handler-case (symbol-function ...) ...), use fboundp instead.
Fix no-overlap test on sbcl, add type checking for data argument of tcp-connect.
Fix write-sequence to tcp stream on sbcl.
Fix unclear errors when exiting event loop after some improperly failed tcp-connect calls.
Fix compiler warning in event.lisp.

Perhaps should remove 'activate' argument of add-event altogether?
Fix compiler warning and possible runtime problem in event-loop.lisp.

run-event-cb makes use of _evcb-err which is provided
lexically by catch-app-errors, so don't try to
compile run-event-cb outside catch-app-errors.
Fix tcp-connect-fail test.

Sometimes it gives 'timeout' and sometimes 'connection refused' error.
Added .gitignore.
tcp-server-close test: don't try to connect if the server wasn't created.
Separated streamish from socket.

streamish is an uv stream wrapper.
Separate socket and server from tcp-socket and tcp-server.
tcp-stream -> async-stream, more general stream stuff.
Added pipes.
Some preliminary process-related code.
Replace MAKE-FOREIGN-TYPE with WITH-FOREIGN-OBJECT*.

Use accessors instead of slot names because accessors are exported
from UV-A package.
Use dynamic context instead of lexical one for CATCH-APP-ERRORS.