Add missing 'on the right' to exit instructions.

[willwhite]

Fixes consistency so we're announcing on the right for all instructions. The more verbose alternative to #124.

[freenerd]

I still think this is too verbose and we clutter 99% of cases, to cover a 1% case. My ideal design as mentioned in #116 (comment):

remove the direction (on the left/right) from instructions, except when we have no way/destination/exit at all: Take the ramp on the right.

This is because I'd prefer this project to err on the side of being as concise as possible, since an annoying, too-verbose nav to me is worse than a too-concise nav (where the user can still look at the screen if I'm unsure). I understand though that this my own opinion and there may be no objective wrong or right.

Ideally we would eventually solve this by knowing the driving-side of the current country (upstream Project-OSRM/osrm-backend#2772) and emit the direction only on divergence of the country norm.

[freenerd]

From a code side, this looks okay. Changelog entry is missing.

[1ec5]

I still think this is too verbose and we clutter 99% of cases, to cover a 1% case.

Concision is good in general, but not at the expense of omitting information potentially relevant to safe driving. I agree that left-hand exits are a minority case (in right-handed countries), but that’s precisely why it’s so important that we inform the user of a left-hand exit. Ambiguity is only part of the problem; a wrong-sided exit requires a lot of additional time to get into the correct lane, because it branches from the fastest lane rather than the slowest.

As a thought experiment, let’s suppose we gain the ability to tell whether the left-hand exit is an anomaly, but a particular instruction needs to be abridged to fit in the allotted time (mapbox/mapbox-navigation-ios#331). In that case, it might be better to omit the exit number or destination (assuming there’s a ref) than to omit the fact that the exit is on the wrong side.