Added kernel + libl4 changes for full and extended ipc.

- Short ipc working as normal. Full/extended ipc haven't been tested.
- Added automated compilation and inclusion of test executable in test0.

tasks/test0/include/linker.lds

@@ -33,9 +33,9 @@ SECTIONS
 	.data : AT (ADDR(.data) - offset)
 	{
 		. = ALIGN(4K);
-		_start_test1 = .;
-		*(.test1)
-		_end_test1 = .;
+		_start_test_exec = .;
+		*(.testexec)
+		_end_test_exec = .;
 		*(.data)
 	}
 	.bss : AT (ADDR(.bss) - offset) { *(.bss) }