Update applyPatch function and add tests for it

[Jan-PieterBaert]

The applyPatch function had a few small bugs when I tried it, so I fixed those and added tests for the function

[angelo-v]

Hi and thanks for your contribution. Can you please describe what bugs you experienced and how your changes fix those?

[Jan-PieterBaert]

The bugs I found:

• the substitute function of a collection didn't seem to work with the current constructor, creating a new collection and adding the elements did work
• in the applyPatch function patch['insert'] was always used, but in the function declaration it said 'patch'
• the ds = ds.statements line meant that if there was a where clause this statement would be executed twice instead of once which meant there would suddenly need to be a ds.statements.statements
• since the other functions seem to assume ds is a collection and the elements of a collection are accessed via elements and not statements I edited that as well
• the targetKB.query function failed because the initBindings was always undefined, the code seemed to assume it's a list so I made it an empty list

[timbl]

Looking back at this now it is merged (and broken for solid-ui.) ds was designed to be an Array, not a Collection - which code expects it to be a Collection?

[timbl]

So the test is wrong too. The parameters are expected to be IndexedFormulas, not collections. Let's roll this back. Sorry I don't read it carefully in review.