[FileSystem] Move hard-coded implementation out of brackets.js

[gruehle]

Currently, the FileSystem is initialized with a hard-coded impl in brackets.js. At minimum, this initialization should be factored out into a separate file. It would be nice if the impl could be declared in a config file (along with other inBrowser-related features).

[gruehle]

To me, medium priority for Sprint 34.

[busykai]

Thank for filing this issue. I was thinking about bootstrapping too. The config should probably be a resource loadable through requirejs/text.

[gruehle]

As noted here, we currently do not wait for the init callback to be called before continuing with startup. We should decide if the callback is needed or not, and if so, do we need to wait for it to be called before continuing.

[jasonsanjose]

Confirmed fixed. Closing.