At the moment, the system property "java.i

At the moment, the system property "java.io.tmpdir" has for value "/tmp" and "/tmp" doesn't exists.

For a first fix, I will assign the property to "/jnode/tmp" and create this directory that will be in the ramdisk (located at /jnode).

After, we will need further discussions on the strategy to adopt. Whatever is the hardware, we need a temp dir and it can only be located on a writeable non-removeable device.

Here is the possibilities I see :
- no mass storage but a ramdisk (not sure it is always created but we can force it to be) : use the ramdisk
- a mass storage : use it for temp dir
- a mass storage and a ramdisk : I think it is preferable to use the mass storage because it generally offers more available space.