Performance improvements and correctness updates

Vanta continues to track changes in the main Klisp implementation and add minor performance improvements.

Correctness updates against thesephist/klisp

• 5637e58 Make = variadic to match new behavior in Klisp
• a5e4435 Add support for predictable tail call optimizations, compliant with Klisp spec
• 63af1d3 Add builtin functions string->symbol and symbol->string
• 20e9138 Fix number->string to print integers without decimals, compliant with Ink based Klisp
• 5195c7b Ensure string values are printed correctly with escape chars
• 5a2796e Add builtin functions, gets and sets!
• d96e1ab When printing functions and macros, print its definition

Performance optimizations

• eaa21b2 Make the value type tag a uint8, not an int32
• 3a24087 Make symbols use an immutable string as its value, not []byte
• 55be986 Intern runtime values of (), true, false
• 6c1e3a6 Avoid needless copying of function parameter lists

As with before, a Linux x86_64 binary is attached with this release.

First release

It works (more or less).

The Linux x86_64 binary is attached :)