Document --config flag (support for multiple config files)

[digitalcraftsman]

The --config flag allows users to specify multiple config files via the CLI.

See gohugoio/hugo#3532

[XhmikosR]

I was just looking for this, but thankfully Google pointed me to the issue and then to the PR and then here :)

[regisphilibert]

Hi! I’m willing to add this to the doc. I may come back with questions here.

Thanks.

[regisphilibert]

Sorry about that. GitHub thinks CLOSE and COMMENT buttons should be on the same level...
I will fork and do a proper PR as I suppose the use of next branch was for emergency edit like Page Resources.

[kaushalmodi]

@regisphilibert While working on this spring cleaning commit c87c9c6, I thought of taking care of this by adding few lines.

[kaushalmodi]

@regisphilibert Oops, just found this PR of yours, part of which took care of this: https://github.com/gohugoio/hugoDocs/pull/323/files#diff-f187629d6a90eae0945fddfe86ae3f90.

[regisphilibert]

Sure this is how I worded it this pending PR gohugoio/hugo#4370:

config file(s), multiple files (a.toml,b.toml.c.toml) will be merged (default is path/config.yaml|json|toml)

[regisphilibert]

@regisphilibert Oops, just found this PR of yours, part of which took care of this

Actually I moved the string directly into a PR on https://github.com/gohugoio/hugo because the part I edited in the doc was generated by Hugo.

[kaushalmodi]

OK, cool. I believe that we are good then. The content/commands/hugo.md will auto-update when that PR is merged. I modified only the manually maintained configuration.md.