first usable version of kernel and commands

After an year of hard work, this is a first "usable" version of Jehanne.

sys/include/plumb.h

@@ -0,0 +1,59 @@
+/*
+ * This file is part of the UCB release of Plan 9. It is subject to the license
+ * terms in the LICENSE file found in the top-level directory of this
+ * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
+ * part of the UCB release of Plan 9, including this file, may be copied,
+ * modified, propagated, or distributed except according to the terms contained
+ * in the LICENSE file.
+ */
+
+#pragma	lib	"libplumb.a"
+#pragma	src	"/sys/src/lib/plumb"
+
+/*
+ * Message format:
+ *	source application\n
+ *	destination port\n
+ *	working directory\n
+ *	type\n
+ *	attributes\n
+ *	nbytes\n
+ *	n bytes of data
+ */
+
+typedef struct Plumbattr Plumbattr;
+typedef struct Plumbmsg Plumbmsg;
+
+struct Plumbmsg
+{
+	char		*src;
+	char		*dst;
+	char		*wdir;
+	char		*type;
+	Plumbattr	*attr;
+	int		ndata;
+	char		*data;
+};
+
+struct Plumbattr
+{
+	char		*name;
+	char		*value;
+	Plumbattr	*next;
+};
+
+int			plumbsend(int, Plumbmsg*);
+int			plumbsendtext(int, char*, char*, char*,
+					 char*);
+Plumbmsg*	plumbrecv(int);
+char*		plumbpack(Plumbmsg*, int*);
+Plumbmsg*	plumbunpack(char*, int);
+Plumbmsg*	plumbunpackpartial(char*, int, int*);
+char*		plumbpackattr(Plumbattr*);
+Plumbattr*	plumbunpackattr(char*);
+Plumbattr*	plumbaddattr(Plumbattr*, Plumbattr*);
+Plumbattr*	plumbdelattr(Plumbattr*, char*);
+void			plumbfree(Plumbmsg*);
+char*		plumblookup(Plumbattr*, char*);
+int			plumbopen(char*, int);
+int			eplumb(int, char*);