We should  use the empty values above before adding more.
We should ignore the case to allow anything that look like "xml".
The struct lttng_version should not be in lttng.h but rather in mi-lttng.h.
Thus padding won't be necessary. Also, uint32_t is preferred to int.
Refactor the name to mi_lttng_version according to the mi namespace.
Create a function to print the mi (print_mi()) since we *may* support  many output type.
This allow to handle the mi writer destruction in one specific call.
Also, cleaner in the long run.
Remove the default return values in mi_lttng.c.
Don't need the HIDDEN attribute since they are assigned in the C file.
Just "return config_writer_write_element_unsigned_int(...)