Particle type syntax highlighting

[repositony]

Particle types could be highlighted for cards like:

phys:n  100.0 1.0e-9
mode n p
imp:n=1.0 
imp:n,p,h=1.0  

This will take some thinking about due to all the ways these can be input. i.e.

• space delimited N P, N P
• comma separated N,P
• part of cards PHYS:N
• multiple on card FMESH34:NPE, FMESH34:N,P,E, etc...
• mode card MODE N P, MODE N, P, etc...

Should be able to generalise most cases fairly easily, but it will probably require some effort to limit to valid types and avoid conflicts with other rules.