Add option for LF line endings to OneLocBuild task

[jonfortescue]

OneLocBuild recently added the option to use LF line endings when checking in files. This is good bc most repos will want to use this, I believe. Nice!

To double check:

• The right tests are in and and the right validation has happened. Guidance: https://github.com/dotnet/core-eng/tree/master/Documentation/Validation

[riarenas]

Question about making true the default.

[jonfortescue]

@riarenas CRLF seems to be wrong for most repos; that's what it is currently and it results in horrid whitespace changes and requires manual normalization to fix across all the repos I've worked with so far.

[riarenas]

That makes sense, and it makes it sound like like we really need this, and it's more of a real fix than a nice to have.

[riarenas]

CRLF seems to be wrong for most repos

Do you know of any repos where it's not wrong? If so we should have those on radar so that they don't get surprised by the new default.

[jonfortescue]

@riarenas nope, there haven't been any so far lol.

[ChadNedzlek]

Why can't we just use the .gitattributes in the repo to do the right thing? Why make this data duplicated there?

[jonfortescue]

@ChadNedzlek The OneLocBuild task is not able to do that, unfortunately

[ChadNedzlek]

It's a little weird that it's somehow bypassing that behavior already. shrugs I guess thems the breaks.