Create console command to view global config

[carbsrule]

Currently an administrator can update the Oro config via the CLI using oro:config:update

This adds oro:config:view which enables viewing the current config

[mbessolov]

Hi @carbsrule

Thank you for your contribution, it could be quite useful for some developers/adminstrators.

In order for this to be accepted though, it needs some additional changes:

1. Properly support output of different data types. If some value cannot be pretty-printed, the command should indicate it.
2. It should properly handle (i.e. not show) sensitive values - if the value is masked in the system configuration UI, it should be masked in this command's output as well.
3. Tests - please look at how other commands are tested. Most likely we will need a functional test and a unit test to properly cover the (updated version of) this command.

Thank you

[carbsrule]

@mbessolov

1. Pretty printing is simple enough and I have (uncommitted) code to handle array|object|bool configs
2. Seems possible using oro_config.provider.system_configuration.form_provider (Oro\Bundle\ConfigBundle\Provider\SystemConfigurationFormProvider) to work out how the field is configured, although TBH I'm not sure if this is desired behaviour. The oro:config:update command is completely unaware of the system config UI, and thus, for example, will dump a plain text value into a field which is meant to be encrypted, so for me it makes sense for this mirror command to behave in a similarly unaware fashion. A user who has access to the CLI likely has access to the DB anyway, so this is just (meant to be) a convenient way of grabbing the value without needing to write an SQL query or manually decode the value. Thoughts?
3. I haven't looked at this yet but can do so

[carbsrule]

@mbessolov I've blocked access to encrypted fields (a possible improvement would be to support a --decrypt flag which would display an encrypted value as though the data were unencrypted), and have added unit and functional tests. I think this is ready, at least for my purposes.

[mbessolov]

@carbsrule thank you, looks great.

Please review and sign the contributor license agreement at https://oroinc.com/b2b-ecommerce/contributor-license-agreement/ so that we can merge you contribution to Oro codebase.