Revert new experimental libev backend due to time constraints

Due to time constraints I had to revert the new libev backend to the
service, I/O and signals monitor.  Employed instead is the tried and
tested signals based service monitor, with a small extension for an
additional I/O monitor using poll() for the I/O plugins to use.

Tried restoring the startx finit.conf directive on top of the service
implementation. However, it's currently not usable to run /usr/bin/startx
for any other user than root. I recommend using the examples/finit.conf
and run /usr/sbin/gdm instead.

finit.c:
        New run_loop() function, replaces libev ev_run().

helpers.c:
        Refactor start_process() into svc_start().

plugin.c:
        Add fds[] array for use in the io_monitor() called by the
        new run_loop().

signal.c:
        Ignore SIGCHLD. Handled by waitpid() in svc_monitor() now,
        which is called by the new run_loop().

svc.c:
        svc_register(): Optional @username parsing for the command line.
        svc_monitor(): Replaced libev callback with waitpid()
        svc_start(): Refactored to use most of helpers.c:start_process()

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

finit.c

@@ -22,10 +22,11 @@
  * THE SOFTWARE.
  */
 
-#include <ctype.h>
 #include <sys/mount.h>
+#include <ctype.h>
 #include <dirent.h>
 #include <linux/fs.h>
+#include <sys/stat.h>		/* umask(), mkdir() */
 
 #include "finit.h"
 #include "helpers.h"
@@ -60,10 +61,18 @@ static void parse_kernel_cmdline(void)
 	}
 }
 
+static int run_loop(void)
+{
+	while (1) {
+		svc_monitor();
+		io_monitor();
+	}
+
+	return 0;
+}
+
 int main(int UNUSED(args), char *argv[])
 {
-	struct ev_loop *loop = ev_default_loop(0);
-
 	/*
 	 * Initial setup of signals, ignore all until we're up.
 	 */
@@ -133,7 +142,7 @@ int main(int UNUSED(args), char *argv[])
 	 * Load plugins and run first level hooks.
 	 */
 	_d("Loading plugins ...");
-	load_plugins(loop, PLUGIN_PATH);
+	load_plugins(PLUGIN_PATH);
 
 	_d("Running first level hooks ...");
 	run_hooks(HOOK_BASEFS_UP);
@@ -183,9 +192,7 @@ int main(int UNUSED(args), char *argv[])
 	 * Enter main loop to monior /dev/initctl and services
 	 */
 	_d("Entering main loop ...");
-	ev_run(loop, 0);
-
-	return 0;
+	return run_loop();
 }
 
 /**