Better error handling in corner cases.

The app was crashing badly upon bogus input.

ie, unreachable URL's, URL'sthat aren't specs at all.

Fixed a couple of rules that were crashing in such cases.

Catching root errors sooner; good handling and proper user feedback is still missing, but at least it isn't crashing.
throw an error if body of the targetted url is empty
clear error messages before each run
fix options var name
revert changes following validator.js update
Fixed case when URL is inaccessible (it was still crashing).
Merge pull request #46 from w3c/tripu/misc-fixes

Better error handling in corner cases
Merge pull request #47 from w3c/tripu/architectural-changes

First architectural changes
Issues #22 & #25 [WIP]:

help descriptions for rules and reproduce documentation.

Added W3C logo.

Added link to project and source code.

Changing layout of page (options more compact, summary of results).
Issues #22 & #25 [WIP]:

Result summary and progress bar hidden initially.

Changed text on progress bar.

 Layout of inputs more compact.
Issues #22 & #25 [WIP]:

Fixed handling of new "processDocument" parameter.

Minor design & CSS improvements.

First filed on form now gets user focus automatically.