Add an option to open results in a right or a bottom pane

[bencolon]

Convert the openProjectFindResultsInRightPane option to a more flexible openProjectFindResultsInANewPane option to open results in a new right OR bottom pane.

This update requires an Atom engine >=1.2.0 because it's using a workspace API update released from 1.2.x

About migrating the old option to the new one, I'm not sure the four lines I've added at the top of lib/find.coffee is the right way. It works but feel free to suggest me a better solution if needed.

Fix #585

[benogle]

Cool. This needs a reviewer

[acontreras89]

This has been recently proposed for the markdown-preview package in atom/markdown-preview#368, although for all directions.
As of now, splits for left and up cannot be achieved in these scenarios, but if we come up with something we could definitely use the same strategy in both packages and keep them consistent.

The easiest way would be to modify Workspace's open method to be able to create new panes in those directions, but that would freeze both PRs for a bit.

[bencolon]

I see your point @acontreras89 but is it really make sense to open a search results panel at the top or on the left ? Only right/bottom should cover 95% of the use cases.
And from a UX perspective, it seems weird to open a new panel "over" the code you're working on.
Thoughts ?

[acontreras89]

Only right/bottom should cover 95% of the use cases.

Agreed. I believe the PR I pointed to will be only adding options for using right/bottom panes, too.

I just wanted to cross-reference them to keep an eye on the topic, my main concern being that both PRs should share the same strategy and be consistent in the implementation. This aside, I'll be OK with pretty much any approach you end up taking.

[lee-dohm]

What's the status on this?