update js samples to use the new org.jetbrains.kotlin.js gradle plugin

[robstoll]

Platform (jvm, js, android): js
Extension (none, kotlin 1.3, jdk8): none

Non-Code related feature

The current samples for mocha and jasmine had been based on kotlin-examples which used the old kotlin plugin. By now, there is a new kotlin plugin (kotlin-examples is not updated though) but we could try to use the new Plugin instead.

The new plugin claims to have a few advantages

The plugin also provides useful testing features, for example:

• Source maps generation
• Test reports generation
• Test run results in the console

So that sounds good. I guess it should be easy for mocha as the default runner they use is mocha but it might actually be hard for jasmine. Therefore I suggest to start with mocha only (first PR) and try afterwards if there is a way to reconfigure the plugin to use jasmine instead (second PR).

Following the description by JetBrains:
https://kotlinlang.org/docs/reference/js-project-setup.html

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[developerfred]

I'll work on this

[robstoll]

@developerfred nice 🙂
I just pushed some cleanups #474, please fork again or rebase on master once it is merged

[developerfred]

thanks @robstoll.

[robstoll]

@developerfred un-assigning so that pthers can take over. Let me know in case you still work on it.

[pablohildo]

I'll work on this.

[robstoll]

@pablohildo unassigning you so that others could take over

[chadmarchand]

I'll work on this