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

build/scripts/Targets/TargetDescriptionFiles/Services/Xml/ToXmlService.php

@@ -70,6 +70,10 @@ class ToXmlService
         $element->setAttribute('start', $this->stringService->tryIntToHex($addressSpace->startAddress, 8));
         $element->setAttribute('size', $addressSpace->size);
 
+        if (!empty($addressSpace->unitSize)) {
+            $element->setAttribute('unit-size', $addressSpace->unitSize);
+        }
+
         if (!empty($addressSpace->endianness)) {
             $element->setAttribute('endianness', strtolower($addressSpace->endianness));
         }