[#1005] - Expand checkstyle to all modules (root).

[damonxue]

fixes #1005
Reformatted all the code to conform to checkstyle rules

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[damonxue]

#1059

[damonxue]

• The reason for formatting too many files is to make sure that they all end with 'lf'.

  I rolled back *.md, *.yml and others not need formatted.

• I will change too many 'lineLength'.

@lprimak @bmarwell pls review.

[lprimak]

Hi, @damonxue
Can you please check the license-related boxes in the PR that I have updated.
Thank you

[lprimak]

I have started the review process. So far it looks great!

[lprimak]

One comment:
You are still trying to do way too much. I will fix it up, but you are just creating extra work for the reviewers unnecessarily.
Because you reformatted pretty much every file (many unnecessarily) you have trampled on some recent changes.

[lprimak]

Also, please do not close this PR, force-push or open another one, or make more massive changes. I can't devote 5+ hours to start from the beginning again.

Thank you!

Overall, great job, we are close to approval.

[fpapon]

@damonxue can you squash the commits and rebase from main?

[fpapon]

@damonxue thank you for the great work!

[lprimak]

@damonxue please don't squash the commit just yet. I will let you know. I am not done with my review / changes.
Once I am done, I will let you know, or maybe do it myself :)

[lprimak]

@damonxue I am done with my changes. Feel free to squash the commits, or let me know if you want me to do it.
Either way is fine with me.

[lprimak]

Looks great!

[lprimak]

I have rebased & squashed the commits. Should be good to go tomorrow :)