CLI: added option to check a single import source or sync rule by name

[log1-c]

Did a (possibly quick and dirty, as I'm not experienced in PHP) implementation of a new --name parameter to make it possible to check a single import source or sync rule with the cli command.

[log1-c]

Issue birthday is nearing, so I'd like to ask for a current state.
Is there a plan to implement this (or something similar)?

PR Works:

boldly pinging @lippserd @Thomas-Gelf

[lippserd]

@log1-c PR will be reviewed next week.

[lippserd]

I think it makes sense to add an option to filter check targets by name. Since jobs also have a name, we could also support the filter here. With the current implementation, the combination of --name with --check deployment or --check jobs would fail in my opinion, as the corresponding filter parameter is missing for the functions. Anyway, I would like to have an implementation that provides roughly the following:

• Support for multiple specification of --name. Wildcards should also be supported.
• Analogous support for the specification of --exclude-name.
• Trigger an error if --check deployment or --check config and --*name are specified.
• Support filter arguments without having to specify --check so that it applies to sync, import and jobs.
• Create a filter object from the specified filter arguments.
• Apply the filter in the corresponding health check functions.

All in all, these changes are not trivial, so I would keep them to a minimum so that we get something done here:

• Raise an error when --name is specified with --check deployment or --check config, i.e. $this->fail('--name is not supported with --check ...');
• Support filtering of jobs.
• Fix code style and indentation 😉.

@log1-c if you need any help with the changes requested, please let me know.

[log1-c]

@lippserd
Thanks for the feedback.

I've done the requested changes regarding the variable naming and the if clauses.
I also added a basic check to raise an error if --name is used with --check deployment or --check config.
I have no idea what the whole filter stuff means or even could look like, sorry.