Add skipImages and skipCss to launchPuppeteer() about crawlee

[mnmkng]

This cannot be reliably done before we have a middleware system for request interception: #204 since it cannot be done on Chromium level (with a flag) and adding request interception prevents adding more request interceptions.

I'm just gonna drop a doc here for referencing it later perhaps:

@param {Boolean|Array} [blockResources=false]
 *   Uses the [`Apify.utils.puppeteer.blockResources()`](../api/puppeteer#puppeteer.blockResources)
 *   function to block downloads of resources such as images, videos or CSS. It accepts either
 *   a boolean `true`, which will enable the default blocking or a `string[]` listing
 *   the resources that should be blocked. See the
 *   [`Apify.utils.puppeteer.blockResources()`](../api/puppeteer#puppeteer.blockResources)
 *   for details.

[jancurn]

This should go to the new class called PuppeteerEx - see other issue.

[jancurn]

Now we have new Apify.utils.puppeteer namespace for this!

[jancurn]

And now we even have Apify.utils.puppeteer.blockResources() that can be used. Perhaps we can only add option blockResourceTypes to launchPuppeteer and that's it.

[mnmkng]

Since request interception disables cache, this might not bring the expected benefits. Closing for now.