[XeTeX] Bold unit vectors

[Nicholas Oettle]

Thanks for all the input.

Whilst I agree that it's not strictly necessary to have the hat over the unit vectors since I'm not defining anything in a particularly unusual way, it is in fairly common usage to see this form. Also, if I were to define a unit vector as:

$\mathbf{\hat{a}}=\frac{\mathbf{a}}{\lvert\lvert\mathbf{a}\rvert\rvert}$

I would have no problems, it's only because i (and j) happen to have a dot on top that difficulties are encountered. I'm unsure as to how the Soft_Dotted property should work, since if I do indeed try to do what I'm aiming to do with a plain i as opposed to \imath, I get a nasty clash. 

$\mathbf{\hat{i}}=\frac{\mathbf{i}}{\lvert\lvert\mathbf{i}\rvert\rvert}$

Many thanks,

Nicholas