Rewrite the entire code-base

The following changes are focused upon:
- Modularity
- Doing away with globals
- No heap allocations
- Better command line interface
- Switch from Xlib to XCB
- More verbose type definitions
- Implement a single-file config by utilising X-macros

include/main.h

@@ -0,0 +1,14 @@
+#pragma once
+
+#include <signal.h>
+
+#include "block.h"
+#include "config.h"
+#include "util.h"
+
+// Utilise C's adjacent string concatenation to count the number of blocks.
+#define X(...) "."
+extern block blocks[LEN(BLOCKS(X)) - 1];
+#undef X
+
+#define REFRESH_SIGNAL SIGUSR1