Finished adding untested bare functionality vfs

Finished adding untested shm syscalls.
Finished adding untested l4 send/recv helpers

Everything compiles. Now going to fix lots of bugs ;-)

tasks/fs0/include/bdev.h

@@ -0,0 +1,8 @@
+#ifndef __BDEV_H__
+#define __BDEV_H__
+/*
+ * This is a mock-up compiled in blockdev buffer, to be used temporarily.
+ */
+
+void *vfs_rootdev_open(void);
+#endif/* __BDEV_H__ */