Update year of copyright in LICENSE to 2018

[aaaaalbert]

• What does this PR do?

It updates the year of copyright given in the LICENSE file from 2017 to 2018.

• Are there points in the code the reviewer needs to double check?

Not applicable, no code was changed.

• Who do you think should review this PR?

Anybody can. It's a trivial edit.

• Why was this PR needed?

A sample document we expect to be reused across projects contained a small error.

• What are the relevant issue numbers fixed (add one line for each)?

None.

[aaaaalbert]

Come to think of it, do we want to include the date in copyright statements at all?

[vladimir-v-diaz]

We use a date range for the copyright statements included in TUF source files.
https://github.com/theupdateframework/tuf/blob/aa2ab218f22d8682e03c992ea98f88efd155cffd/tuf/sig.py#L3

Perhaps we should do the same for the LICENSE sample doc?
For example,

Copyright (c) [year file was created] - [last year file modified] Secure Systems Lab at NYU

[aaaaalbert]

Yes, that's a popular style I suppose.

Wikipedia tells me we don't really need copyright notices, though:

• https://en.wikipedia.org/wiki/Copyright#Copyright_notice
• https://en.wikipedia.org/wiki/Copyright_notice

[vladimir-v-diaz]

If there a good reason to not include the optional copyright notice? I think it wouldn't hurt to include one. It seems to be the popular choice with open source projects, companies, etc., and according to the Wikipedia: "US law no longer requires the use of a copyright notice, although placing it on a work does confer certain benefits to the copyright holder."

Here are the reasons for including the copyright notice:

A copyright notice may still be used as a deterrent against infringement, or as a notice that the owner intends on holding their claim to copyright.[1] It is also a copyright violation, if not also a federal crime, to remove or modify copyright notice with intent to "induce, enable, facilitate, or conceal an infringement".[2] Also worth noting is that copyright notice has never been required on "unpublished" works, the copyright of which may last for well over 100 years.

Inclusion of a proper copyright notice on the originals is also evidence that the copyright owners may use to defeat a defense of "innocent infringement", to avoid "statutory damages", other than in certain cases claiming a "fair use" defense.[3]