Brighten the caret on the select icon

[dennisreimann]

Reuses the body text muted color. Closes #38.

Before

After

[dstrukt]

I've been doing a lot of mobile testing, and did some more on the plane, will be filing a few little issues for either one of us to patch up.. but noticed this, might just be Chrome mobile browser overrides, not sure. Very minor, and not required to merge the above changes, but was curious and thought I'd document.

[dennisreimann]

Oh that's strange, thanks for the pointer! Might be related to the additional functionality of the currency selector – I'll investigate.

[dennisreimann]

Fixed it, good to go now!