Make use of Dash's new CamelCase convention to lookup words that contain whitespace

Recently, Dash has introduced a new convention that allows the reliable lookup of entries that contain whitespace:

> To lookup `foo bar`, perform a Dash search for `fooBar`.  Internally, Dash will convert back and correctly search for `foo bar` entries in its docsets.

Such lookups of multiple (whitespace-separated) words didn't work correctly before.