Fix broken samples

[AntonioND]

While working on #231 I've found the following issues:

The following samples are broken: languages/nodejs (Abort), languages/openmp (The test program hangs).

Also, in containers/encrypted, the Makefile targets run-hw-integrity and run-sw-integrity don't seem to work.

Finally, regarding languages/java, it prints a test message and then it hangs. I'm not sure what the expected behaviour is, but I would expect it to print it and exit. It just seems to hang after printing it.

EDIT: Also, the ml samples don't work with ETHREADS=1.

[prp]

• languages/nodejs is currently broken because of Fix detached pthread failures #779. Hopefully this will be fixed soon.
• languages/openmp is broken because of GCC OpenMP applications fail due to direct futex syscall instructions #535. This is due to a fundamental incompatibility, as documented here: https://github.com/lsds/sgx-lkl/blob/oe_port/docs/Incompatibilities.md#calling-system-calls. A possible workaround would be to move to a different OpenMP runtime that doesn't issue direct system calls.
• languages/java has issues because of Incomplete/unsafe signal handling with SGX1 #680.

[AntonioND]

The languages/java sample has been fixed by setting the number of ethreads to 4 in #829.