Improve maintainability of source code files about community

[bmuenzenmeyer]

The README I am less sure of (and since there is only one it doesn't matter as much to me), but I like the file name change

[wass3r]

we'll go with the option to remove the copyright piece from the source files. i'll open an example PR to a repo of what the change will look like for the other repos.

[bmuenzenmeyer]

I wonder if it could be automated

[wass3r]

oh yes. it will be. i just want to make sure i understand what the change will look like.

in fact. i'm wondering about replacing our standard three-liner in our code files:

// Copyright (c) 2022 Target Brands, Inc. All rights reserved.
//
// Use of this source code is governed by the LICENSE file in this repository.

with a SPDX identifier, such as:

// SPDX-License-Identifier: Apache-2.0

more info: https://spdx.dev/ids/#why

In our README's in the repos, also looking to reduce:

## Copyright and License

Copyright (c) 2022 Target Brands, Inc.

[Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0)

to just:

## License

[Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0)

do you have any thoughts on those tweaks?

[wass3r]

Here's an example of the changes I was thinking to make: go-vela/vela-email#41.

couple of callouts:

1. https://github.com/go-vela/vela-email/pull/41/files#diff-c693279643b8cd5d248172d9c22cb7cf4ed163a3c98c8a3f69c2717edd3eacb7R189 follows guidance here more closely: https://www.apache.org/licenses/LICENSE-2.0.html#apply. one contention might be the year i picked. was hoping to keep this the same across all repos, but it may differ per repo, depending on what it needs to be.
2. curious on thoughts for https://github.com/go-vela/vela-email/pull/41/files#diff-70d86781add4b013df40d3433bf0ed8033639b5e05fcc2c43d23afe0085d4892R37. took some liberties here maybe, but saw another module do this.

the remainder of the changes are pretty uncontroversial, i think.