Write individual files to output path if it is a directory

[zeeZ]

I created this to solve #897 before noticing #929 and am posting this to maybe offer a simpler alternative.

Current behaviour for -o is to complain if the path is a directory, so I simply changed that to write the individual files (based on the final resource) there instead.

I did not include namespace in the file name because neither ResId.GvknString() nor Gvk.String() include it and I didn't want to write that function a third time and didn't feel the need for it because namespace is usually also set once per build. If it's deemed necessary I'll add it.

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[monopole]

This follows the suggestion in #897, but doesn't do what the requestor wants, i.e.

I need to reproduce an exact file layout as it is needed for our purposes.

Does anyone else want the output split into gvkn.yaml files?

[zeeZ]

There is also #55 with two people wanting split files, though the initial request was also for writing out following the input names. I guess I'm trying to solve neither OP, but the comments, with predictable file names.

[monopole]

/lgtm

[monopole]

/approved

[sidps]

I presume this will be in the next release? If so, when will that be?

[pdefreitas]

I am wondering when this will be released.

Edit: It has been released, however kubectl still ships version 2 of Kustomize which mislead me to think that this feature hasn't been shipped yet.