feat(web-server): serve css files

[timols]

Closes #431

[vojtajina]

Great job @timols, let's fix couple of small issues and we can merge it in:

• address comments
• change the commit msg to something like feat(web-server): serve css files
• into commit msg body, add Closes #431
• fix the style issues (see failing travis https://travis-ci.org/karma-runner/karma/jobs/8448284)

[vojtajina]

can you write this in "node" style:

if (xxx) {
  return util.format(LINK_TAG, ...);
}

return util.format(SCRIPT_TAG, ...);

Also, change the regexp to not match /some.css/folder/file.js:

if (/\.css$/.test(filePath))

[timols]

Great. Thanks for the feedback. I'll fix these issues shortly.

[timols]

@vojtajina I think all items are now resolved. Please let me know if I need to address anything else.

[vojtajina]

Great, thank you very much @timols !

[timols]

Any chance we can get a canary build out for these changes?

[vojtajina]

@bkbiker thanks for reporting this! @timols do you have time to look into it ?

Creating an issue for this #636