Massive refactor to accommodate RISC-V targets

- Refactored entire codebase (excluding the Insight component) to accommodate multiple target architectures (no longer specific to AVR)
- Deleted 'generate SVD' GDB monitor command - I will eventually move this functionality to the Bloom website
- Added unit size property to address spaces
- Many other changes which I couldn't be bothered to describe here

src/Targets/TargetBitFieldDescriptor.cpp

@@ -0,0 +1,20 @@
+#include "TargetBitFieldDescriptor.hpp"
+
+namespace Targets
+{
+    TargetBitFieldDescriptor::TargetBitFieldDescriptor(
+        const std::string& key,
+        const std::string& name,
+        std::uint64_t mask,
+        std::optional<std::string> description
+    )
+        : key(key)
+        , name(name)
+        , mask(mask)
+        , description(description)
+    {}
+
+    TargetBitFieldDescriptor TargetBitFieldDescriptor::clone() const {
+        return {*this};
+    }
+}