Support latest PXT with GC (#1798)

* Enable gc and basic compilation fixes

* Add missing GC stuff

* Set microbit-dal version

* Disable jacdac in servo

* UTF fixes

* TS build fixes

* Auto-generated files update

* We only seem to have that much

* Fix for new new compiler

* Account for uninitialized scheduler

* Intialize memory allocator

* bump references

* updated package

* Set image tag, requires https://github.com/Microsoft/pxt/pull/5262

* updated project summaries

* Fixing block tests

libs/core/pxtcore.h

@@ -10,6 +10,11 @@ namespace pxt {
 void debuglog(const char *format, ...);
 }
 
+// #define GC_GET_HEAP_SIZE() device_heap_size(0)
+#define xmalloc malloc
+#define xfree free
+
+#define GC_BLOCK_SIZE 1000
 
 #define DMESG NOLOG