rename lzw module to lzwgif to better reflect what it does

that it's not an implementation for LZW but the GIF-variant/specific
version of LZW

libretrogd/src/graphics/bitmap/gif.rs

@@ -6,7 +6,7 @@ use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
 use thiserror::Error;
 
 use crate::graphics::*;
-use crate::utils::lzw::{lzw_decode, lzw_encode, LzwError};
+use crate::utils::lzwgif::*;
 
 const BITS_FOR_256_COLORS: u32 = 7;   // formula is `2 ^ (bits + 1) = num_colors`
 

libretrogd/src/utils/mod.rs

@@ -6,7 +6,7 @@ use rand::Rng;
 
 pub mod bytes;
 pub mod io;
-pub mod lzw;
+pub mod lzwgif;
 pub mod packbits;
 
 pub fn rnd_value<N: SampleUniform + PartialOrd>(low: N, high: N) -> N {