Use one of the unused time state bits to indicate if an error has
occurred where CFE_TIME_GetReference was not able to get a consistent
copy of the reference state data.

In a functional system this should never occur - there should be at
most one retry, which only happens in the event there was a burst
of updates (more than 4) concurrently with reading the structure.

The previous implementation did not report or handle the condition
at all, this at least sets a TLM status bit and returns a reference
struct filled with all zeros.

Provide the UT_BSP_Lock/Unlock function to be compatible with
nasa/osal#1065.  The library no longer needs to be locked the
entire time a test runs. This also allows test programs to be
multi threaded.

- Now returning `CFE_FS_SetTimestamp` success as `CFE_SUCCESS`
- `CFE_FS_SetTimestamp` now returns `CFE_STATUS_EXTERNAL_RESOURCE_FAIL` if the write doesn't return the correct bytes written
- Update coverage test checks
- Updated the functional test to check for `CFE_SUCCESS` vs `OS_SUCCESS`
- Updated check of status in `cfe_tbl_task_cmds.c` to `CFE_SUCCESS

 #1205: Added task and CDS file write default filenames
 #1131: Removed optional from EVS log
 #1127: Non-parameter reload/restart doesn't increment cmd error
 #1029: Removed system log elements from reset preservation list
 #942: Simplifed table partial load file requirement

Put the "detaildesign" and "users_guide" into separate working
directories, and do a general cleanup/simplification of the generated
doxyfiles.

Detail design just includes all components, and use "exclude" where
special treatment was needed, and to avoid UT code.

Paths for each "arch" (target-specific) are written to separate files
and included directly in the generated doxyfile, reducing the number
of generated files/layers.

Use a unique file name for the doxygen warnings, instead
of "warnings.log", so the mutiple documentation targets
will not overwrite the other log file.

Use a prefixed name so that if the log file is uploaded
to the build artifacts, it will be identifiable.

Detail Design warnings in: detaildesign-warnings.log
Users Guide warnings in: cfe-usersguide-warnings.log

Add ${ARGN} such that the user can specify multiple source files

Add a check for targets in the add_cfe_coverage_dependency, so this
can be used to add arbitrary other non-stub libraries too.

In CCB review 2021-06-09 it was agreed this might have unintended
consequences/ordering dependencies so best to leave it alone.

Use "docs" instead of "doc" in both source and binary/build directory
names for documentation and related files.

Fix #1483, Add CI workflow to run cFE coverage tests

Fix #1299, Updated FS Read/WriteHeader API return documentation

Fix #567, Document CFE_ES_RunLoop increment task counter behavior

Fix #1614, standardize on "docs" subdirectory

Fix #1177, Update version description per current design

Fix #741, Document CFE_TBL_Unregister use-case

Fix #1595, provide CFE assert lock/unlock

Fix #1442, Simplify CFE_FS_SetTimestamp and fix syslog typo

Fix #1308, Removed redundant check/set of CFE_CPU_ID_VALUE

Fix #1544, add time get reference error bit

Fix #1199, Add workflow to build cFE documentation

…irements

Fix #1205 #1131 #1127 #1029 #942 - Requirements updates

Fix #1306, ES/ResourceID documentation cleanup

Fix #1490, allow multiple sources in add_cfe_coverage_test

Fix #814, add ES Misc Functional test

…al_Tests

Fix #811, add Mempool functional tests

Fix #1604, Clean/simplify version header and reporting

Fix #1378, 1589, doxygen cleanup

Fix #1325, Prepend system log messages with function name

See #1619 and #265