Allow pipe + redirect in task/run stanzas, exec() in /bin/sh

This patch extends the capabilities of task and run .conf stanzas by
enabling pipes and redirects.

Example:

    task [s] echo "foo" | cat >/tmp/bar
    run  [s] echo "$HOME" >/tmp/secret

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

src/svc.h

@@ -45,6 +45,7 @@ typedef enum {
 } svc_type_t;
 
 #define SVC_TYPE_ANY          (-1)
+#define SVC_TYPE_RUNTASK      (6)
 
 typedef enum {
 	SVC_HALTED_STATE = 0,	/* Not allowed in runlevel, or not enabled. */