add panicking test cases

[0xalpharush]

PR'ing these panics so they can be re-used as regression tests once they're fixed

---- panic_2 stdout ----
thread 'panic_2' panicked at pade/src/primitives.rs:78:1:
range end index 3 out of range for slice of length 0

---- panic_1 stdout ----
thread 'panic_1' panicked at /Users/troysargent/pade/pade/src/decode.rs:136:9:
assertion failed: decode_slice.is_empty()
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

[Will-Smith11]

Looks like there's some conflicts now that I added Rustfmt. If you could fix those and then we can merge this.

[0xalpharush]

rebased and formatted