Update 'build' command to bundle for production

[dafo]

Closes #951
Closes #943
Closes #956

This should not be merged before investigating an issue when a template imports anything from 'igniteui-webcomponents'

Example error:

ERROR in ./node_modules/igniteui-webcomponents/index.js 1:2377-2456
Module not found: Error: Can't resolve './components/icon/icon.registry' in 'C:\work\github\igniteui-cli\output\IG Project 12\node_modules\igniteui-webcomponents'
Did you mean 'icon.registry.js'?
BREAKING CHANGE: The request './components/icon/icon.registry' failed to resolve only because it was resolved as fully specified
(probably because the origin is strict EcmaScript Module, e. g. a module with javascript mimetype, a '.mjs' file, or a '.js' file where the package.json contains '"type": "module"').
The extension in the request is mandatory for it to be fully specified.
Add the extension to the request.
@ ./src/app/badge/badge.ts 1:0-71 1:71-87 1:88-105
@ ./src/index.ts 1:69-98

[coveralls]

Coverage decreased (-1.0008%) to 73.007% when pulling 058747e on amarinov/buildTaskWC into 68a55ff on master.

[dafo]

This is fixed.
More information on that error -> here

[gmurray81]

Seems like that'll do the trick. Personally, I do like there to be a legacy mode so that you can build for older browser like in my example, but I think we were being told we didn't need to support IE111 any longer, and this certainly makes for a simpler webpack config. You might not technically need to force lit-html through babel if not supporting older browsers. The main reason I was doing that was because lit-html ONLY distributes esm modules, so in order to make them usable in ie11, they needed to be fed through babel. Similarly, you may not need to feed our stuff through babel either. You may be able to change the exclusion so that it just excludes all of node_modules.

Unless you want to try to add the legacy support, I'd see if it works fine by just excluding all of node_modules in the exclude statement