Add 2 mm and 2.1 mm mounting holes

[diegoherranz]

Modified from other existing mounting holes.
Thanks.

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[poeschlr]

Which screws would fit these mounting holes?

[diegoherranz]

I needed this to be used with plastic locating pips on a moulded plastic part. So, it didn't make sense to mention any screw size.
I've seen there are many mounting holes on this library which only reference the actual hole size and no screw at all, leaving the decision to the user and I guess that's OK?
Thanks!

[poeschlr]

I was mainly confused as i thought you might have intended these to be used for M2 screws.

[poeschlr]

Thanks for your contribution and sorry it took so long.

[diegoherranz]

Not a problem. The important thing is that it eventually gets merged.
Thanks again to the good work by the librarians.