engineering notation symbol (#669)

[hookdump]

Changed the symbol E to ᴇ.

[erosson]

(I'm really sorry for the delay. Haven't been able to work much lately.)

Thank you!

Some comments before I merge this:

• Input (parsenumber.coffee) also needs to accept ᴇ so copypasting works. Replacing /ᴇ/e/ in the input would probably do it
• Use ᴇ instead of a literal ᴇ to avoid file encoding issues later

I don't mind doing these myself if I find the time before you do.

Also, checking since this is your first contribution: Swarmsim's GPLv2 licensed, I assume you're posting this under the same license?

[erosson]

Sorry I didn't get to this sooner, but this code's moved to swarm-numberformat and this patch no longer applies.