Switch bundling to use rollup

[realityking]

This is an alternative to #541

The main advantage is a vastly smaller bundle (minified version is 1.5 kB or 15% smaller) but using rollup will also make it easier to ship CommonJS and ESM versions of Clipboard.js.

The main reasons why the build is smaller are:

• All modules inlined together, removing a lot of overheard
• Babel helpers are only included once
• Individual modules are not converted to UMD modules before bundling

[jpike88]

One month later, nothing.

@zenorocha appreciate some sort of comment here

[zenorocha]

Sorry, at this moment I don't have the time to review it.

[veeramarni]

@realityking Thanks for the PR. I believe we need to apply this PR quickly as the clipboard started failed with following errors when using latest webpack@4.19.01 in our project.

@zenorocha Please share your thoughts on this. If you do need time then we plan to create a temporary package until it is official from you.

[jpike88]

@zenorocha if you don’t have the time to review PR, it’s probably a good idea to grant someone else the ability to do so

[jpike88]

@veeramarni if nothing gets done let me know what npm package you're calling it, I'll just switch to that

[veeramarni]

If anyone needs it quickly, here is the package I have created.

cdm-clipboard@2.0.1

[zenorocha]

Hey guys, sorry for the delay. I really appreciate your effort.

I decided to migrate to Webpack 4 instead since it's a tool that has been more adopted by the community. Please try the new version 2.0.2 and let me know if it's working for you.

Thanks!