< and > not handled correctly in symbols.

[indiejames]

Version 0.4.0
Tested on macOS Sierra v. 10.12.5

Trying to parse repl-test.core/foo->bar results int the following error:

provided an invalid symbol repl-test.core/foo->bar

I notice that this is a result of failing to match the following regex (atoms.coffee) in the Symbols class:

validRegex: /[0-9A-Za-z.*+!\-_?$%&=:#/]+/

This regex does not contain < or >.