Initial import of Flemming Madsen's LibUEvent

This fork is called libuev and will focus solely on embedded Linux
systems using C.  Patches for other UNIX-like operating systems are
welcome.

- Remove Lua support, will not be used.
- Rename from LibUEvent to libuev where applicable
- Add project's MIT license to top of all files, as is customary
- Add a LICENSE file, as is customary

This MIT licensed code was cloned from the Mercurial repository at
Google http://code.google.com/p/libuevent/ which had mislabled the
license as "New BSD License", which is wrong.  The actual license
of the project is https://en.wikipedia.org/wiki/MIT_License

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

README.md

@@ -0,0 +1,39 @@
+libuev - Asynchronous event loop library
+========================================
+
+The libuev library is a small event library in the style of the venerable
+Xt(3) event loop.
+
+Basically an event context is created,and handlers for timeounts and stream
+events can be registered with this context.
+
+After initial setup, the typical application will enter the event loop that
+will only return at program termination.
+
+The C API
+---------
+The typical application will do the following steps
+
+1. Create the event context with lueCtxtCreate()
+2. Register initial callbacks with lueAddInput, lueAddOutput and lueAddTimer
+3. Enter the event loop
+
+Building
+--------
+Use make:
+
+* make all: The library
+* make test: Test and showcase
+
+Installation
+------------
+Is purely manual, but would be something along the lines of:
+ sudo install -m 444 libuev.so.1 /usr/lib/libuev.so.1
+
+Warning
+-------
+Not thread safe!
+
+The ctxt structure needs mutex protection in case of multi threaded
+access.
+