Avoid misleading warning about actually used cmd line options

[nmnobre]

This patch avoids misleading warnings for two IO options, -keep-cout and --drop-cerr, by checking for the command line option on all processors (including the zeroth).

WARNING! There are options you set that were not used!
WARNING! could be spelling mistake, etc!
There is one unused database option. It is:
Option left: name:--keep-cout (no value) source: command line

[jwpeterson]

I thought this was a warning that came from PETSc, and there was no way to avoid it since --keep-cout isn't a PETSc option (therefore it is not used as far as PETSC is concerned).

[nmnobre]

I thought this was a warning that came from PETSc

I think it is, but only because we're passing it on to PETSc by failing to consume it within libMesh.

[moosebuild]

Job Coverage on 4fd0e6f wanted to post the following:

Coverage

	80e8b6	#3942 4fd0e6
	Total	Total	+/-	New
Rate	63.42%	63.41%	-0.00%	75.00%
Hits	71940	71939	-1	3
Misses	41502	41503	+1	1

Diff coverage report

Full coverage report

Warnings

• New new line coverage rate 75.00% is less than the suggested 90.0%

This comment will be updated on new commits.

[roystgnr]

Test failures are from a snafu downstream

[nmnobre]

Note to future self, we didn't see this in MOOSE because we're calling libMesh::add_command_line_name() there as well:

https://github.com/idaholab/moose/blob/f5681a9d7aa9ca34b44531bf6331eb7ae4d24886/framework/include/utils/InputParameters.h#L1569-L1586