Move project documentation to its own folder

docs/logger.md

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+# Logging and Debugging Messages
+The logging system is designed to make log messages clearer and improve their uniformity across the project.
+It makes it easier to see where a log message comes from and what its verbosity is.
+
+To use the logging system, include `log.h` in your source file, and use the following macros to print log messages:
+```c
+LOG_DEBUG(TAG, fmt, ...)
+LOG_INFO(TAG, fmt, ...)
+LOG_WARN(TAG, fmt, ...)
+LOG_CRIT(TAG, fmt, ...)
+LOG_FATAL(TAG, fmt, ...)
+```
+The same format specifiers as in `printf` can be used.
+
+The `TAG` parameter is a string that identifies the source of the log message.
+It is recommended to use one tag for each source file / module, and to name the tag after the source file / module.
+See the example below.
+
+## Global Log Level
+You can control the verbosity of the logging output by setting a global log level in `log.h`.
+This log level filters out messages with a lower priority.
+
+## Custom Log Levels
+before you include `log.h`, you can define custom log levels by defining the following macros:
+```c
+// All log messages will be printed
+#define LOGGER_LEVEL_ALL
+#include "log.h"
+```
+
+```c
+// Info and higher priority messages will be printed
+#define LOGGER_LEVEL_INFO
+#include "log.h"
+```
+
+```c
+// Only warnings and errors will be printed
+#define LOGGER_LEVEL_WARN
+#include "log.h"
+```
+
+```c
+// Only log messages with level ERROR will be printed
+#define LOGGER_LEVEL_CRITICAL
+#include "log.h"
+```
+
+```c
+// Only log messages with level ERROR will be printed
+#define LOGGER_LEVEL_FATAL
+#include "log.h"
+```
+
+## Colorful Log Messages
+For improved readability, log messages can be printed in color by defining `LOGGER_USE_COLOR` in `log.h` or before you include `log.h`. \
+Default is `0`
+
+## Log Output Format
+Each log entry is formatted to include the following information:
+
+- Log level ([Debug], [Info], [Warn], [Critical], [Fatal])
+- Timestamp (in milliseconds since boot)
+- Tag
+- The log message
+
+For instance, a log entry may look like this:
+
+`[Info] (2009) [LTDC]: This is a log message`
+
+## Example
+```c
+#define LOGGER_LEVEL_INFO
+#include "log.h"
+
+// Don't use a define for the tag, as the pointer to the tag is used
+static const char *TAG = "main";
+
+int main(void) {
+    
+    LOG_DEBUG(TAG, "This message will not be printed");
+    LOG_INFO(TAG, "This message will be printed");
+    LOG_WARN(TAG, "This message will be printed");
+    LOG_CRIT(TAG, "This message will be printed");
+    LOG_FATAL(TAG, "This message will be printed");
+    
+    for (int i = 0; i < 3; i++) {
+        LOG_INFO(TAG, "Iteration %d of %d", i, 3);
+    }
+    
+    return 0;
+}
+```
+Result:
+```
+[Info]     (2009) [main]: This message will be printed
+[Warning]  (2026) [main]: This message will be printed
+[CRITICAL] (2033) [main]: This message will be printed
+[FATAL]    (2040) [main]: This message will be printed
+[Info]     (2040) [main]: Iteration 0 of 3
+[Info]     (2047) [main]: Iteration 1 of 3
+[Info]     (2054) [main]: Iteration 2 of 3
+```