Simplify reader macro to compiler logic

[chrisrink10]

Every time we want to add a new reader macro to Basilisp, changes need to be made to the reader, analyzer, and generator to support those changes. However, it would probably be much simpler if we merely returned some sort of ReaderMacro type from the reader which the compiler could use to generically reconstruct the reader form, so we wouldn't have to add special support to the compiler for every macro form.