Close #96

Those functions only need system size and they will become a
requirement for mu_init, therefore we avoid circular dependencies.

Now --verbose options affect all libraries, not only debug.
Additionally, some debug macros have been transformed to functions.

Old versions of GCC are too strict with shadowing rules

This binary is used to run applications that may or not be DLB aware,
but will register the current mask before the application starts.

Close #95

This service is used to pre-register a mask into the DLB shared memory

If the shmem exists but we don't have its handler, try to open it
in order to destroy it correctly

Add shmem functions to check if the file exists,
and to destroy it if we don't have access to its handler

Now all C tests will automatically include
assert_noshmem.h and perish.h

Some OMP runtimes do not use the first threads when reducing the
number of threads. Therefore, we need to ensure that all threads
are bound to the right CPU.

On large systems process_mask contained bits further than 64

- ncpus must not be decremented if the CPU is not reclamable
- output arrays were not correctly invalidated

Fix #94

CPU_ISSET may return any integer greater than 1, casting is needed.
Also, simplify the error checking with asserts.

Backtrace functions are GNU extensions.

Close #93

Timestamp last_borrow should only be updated when
the borrow does not succeed

Fix typo
Add and update some comments

Options parsing was not correctly removing "=values"

This option will make warnings to raise a DLB panic error