The previous design was broken, can't multiplex unless there's
a new allocation of ompt_data.
Now, omptool.c manages the task_data and calls omptm or talp using
more high-level functions. It additionally adds pointers to each
module to store private data.

- Remove atexit cleanup
- Monitoring regions are alive after MPI_Finalize as long as the
  user calls DLB_Init before MPI_Init.

- Move bools into a flags type
- Move custom monitoring regions to spd
- Move global monitor into the same list with all other monitors

Fix #208

Includes refactoring of public elements:
- DLB_GLOBAL_REGION macro
- DLB_MonitoringRegionGetGlobalRegion()
- Global region name is now "Application"

[ci-skip]

[ci-skip]

Resolve "Printng DLB variables may cause buffer overflow"

Closes #213

See merge request dlb/dlb!79

More accurate with man description, errno may not be assigned a value.

Update documentation for 3.4 release

Closes #166 and #178

See merge request dlb/dlb!76

- Add LeWI flags
- Add API types (fix #166)
- Add some new TALP functions
- Minor edits