Utils: Introduce utils and animation helpers

The next commit implements the LCD and animation support. To enable an easy
way to create animations for it, add details in the README regarding the way
the SD card is used and how the files need to be formatted.

Create the Utils directory and add a Rust project to do the bit flipping and
a script that automates all the steps described in the README.
Add a README for Utils explaining how to use them.

Utils/bitmap_helper/.gitignore

@@ -0,0 +1 @@
+/target

Utils/bitmap_helper/Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "bitmap_helper"
+version = "0.1.0"

Utils/bitmap_helper/Cargo.toml

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+[package]
+name = "bitmap_helper"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

Utils/bitmap_helper/src/main.rs

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+use std::fs::File;
+use std::fs::write;
+use std::env;
+use std::io::Read;
+
+fn main() {
+    let args: Vec<String> = env::args().collect();
+
+    for arg in &args[1..] {
+        println!("Processing : {}", arg);
+        if !arg.ends_with(".mono") {
+            eprintln!("{} : unsupported file type.", arg);
+            continue;
+        }
+        let file_r = File::open(arg);
+        if file_r.is_err() {
+            eprintln!("{} : could not open file.", arg);
+            continue;
+        }
+        let mut image_data = vec![];
+        if file_r.unwrap().read_to_end(&mut image_data).is_err() {
+            eprintln!("{} : could not read file.", arg);
+            continue;
+        }
+
+        let out_file = arg.replace(".mono", ".bin");
+        flip_bits(&mut image_data);
+        if write(&out_file, &image_data).is_err() {
+            eprintln!("Failed to write bit flipped bitmap to file : {}", out_file);
+        }
+        println!("Processing successful, flipped bits and wrote to {}", out_file);
+    }
+}
+
+/// Flips the bits of each individual byte (except zeroes).
+/// This would transform 0b11001100 in 0b00110011.
+fn flip_bits(data: &mut Vec<u8>) {
+    for source_id in 0..data.len() {
+        let mut new_int = 0;
+        for i in 0..8 {
+            if data[source_id] == 0 { break; }
+            new_int |= ((data[source_id] & (1 << 7 - i)) >> 7 - i) << i;
+        }
+        data[source_id] = new_int;
+    }
+    // for i in 0..data.len() {
+    //     print!("{:2X}", data[i]);
+    //     if i > 0 && i%16 == 0 { println!(); }
+    // }
+    // println!();
+}