First, unindent some of the AST code.
Second, genRandInt is unused; delete it.
Third, genRandIntn is really just mathrand.Intn. Just use it directly.
Fourth, don't use inline comments if they result in super long lines.
Implement a literal obfuscator interface,
to allow the easy addition of new encodings.
Add literal obfuscation for byte literals.
Choose a random obfuscator on literal obfuscation,
useful when multiple obfuscators are implemented.
Fixes#62