Checking in initial baseline for project based on a combo

of Rust templates and content from the embassy project
and including my initial merging of the wifi_tcp_server,
usb_serial, and blinky sample code.

memory.x

@@ -0,0 +1,17 @@
+MEMORY {
+    BOOT2   : ORIGIN = 0x10000000, LENGTH = 0x100
+    FLASH   : ORIGIN = 0x10000100, LENGTH = 2048K - 0x100
+
+    /* Pick one of the two options for RAM layout     */
+
+    /* OPTION A: Use all RAM banks as one big block   */
+    /* Reasonable, unless you are doing something     */
+    /* really particular with DMA or other concurrent */
+    /* access that would benefit from striping        */
+    RAM   : ORIGIN = 0x20000000, LENGTH = 264K
+
+    /* OPTION B: Keep the unstriped sections separate */
+    /* RAM: ORIGIN = 0x20000000, LENGTH = 256K        */
+    /* SCRATCH_A: ORIGIN = 0x20040000, LENGTH = 4K    */
+    /* SCRATCH_B: ORIGIN = 0x20041000, LENGTH = 4K    */
+}