DOC: Improve the copyright notice information in the LICENSE file

[jhlegarreta]

Improve the copyright notice information in the LICENSE file: make the notice specific to this repository and avoid any variability in the notices by removing the placeholders:

• Use the original year (2021) in which works were first released.
• Use the NiPreps name and email address in LICENSE file.
• Remove the explanation related to the placeholders.

Apply the above changes to the copyright notices across source files.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 64.08%. Comparing base (b1d9928) to head (a29ab26).
Report is 9 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #235      +/-   ##
==========================================
+ Coverage   63.97%   64.08%   +0.11%     
==========================================
  Files          18       18              
  Lines         905      905              
  Branches      154      117      -37     
==========================================
+ Hits          579      580       +1     
  Misses        282      282              
+ Partials       44       43       -1     

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[jhlegarreta]

Have been thinking and reading more about this:

• https://www.apache.org/licenses/LICENSE-2.0
• https://infra.apache.org/licensing-howto.html
• https://opensource.stackexchange.com/questions/5778/why-do-licenses-such-as-the-mit-license-specify-a-single-year
• nipreps/fmriprep@fa5cf5b
• Even some of the repositories of the large companies that do software that are listed in the blog post that Chris mentions in his commit message contain inconsistencies, e.g.
  • Netflix folks:
    • https://github.com/Netflix/Hystrix/blob/master/README.md#license
    • https://github.com/Netflix/Hystrix/blob/master/hystrix-core/src/test/java/com/netflix/hystrix/HystrixCollapserTest.java created in 2014; last modified in 2016 and notice year is 2015; license file year is 2013; releases having been created all along those years
  • Go folks:
    • https://github.com/golang/go/blob/master/src/syscall/asm_aix_ppc64.s created in 2018; notice year is 2014; license file year is 2009; no releases but tags being created all along those years.
• VS folks: looks like they do not run that risk: they do not mention any year in the notice on each file and refer to the license fil e.g. https://github.com/microsoft/vscode/blob/main/src/bootstrap-meta.ts

So despite the comment about the year in the 17 U.S. Code § 401 mentioned in https://opensource.stackexchange.com/a/5779, it looks like dropping the year would be OK as mentioned at the Tech Monitoring meeting on Oct 1 2024. Did not add a reference to the LICENSE file though, and followed what the instructions say. the LICENSE file contains anyways the same information as the URL that is pointed on every file.

[effigies]

LGTM. A couple minor suggestions.

[effigies]

LGTM. Given that I proposed removing the license appendix, I'll let someone else merge, if they agree.