Add uPy welcome message to UNIX and Windows ports; update Teensy port.

Partly addresses issue #154.

teensy/main.c

@@ -19,6 +19,7 @@
 #include "usb.h"
 #include "gc.h"
 #include "led.h"
+#include "build/py/py-version.h"
 
 #include "Arduino.h"
 
@@ -380,7 +381,7 @@ bool do_file(const char *filename) {
 }
 
 void do_repl(void) {
-    stdout_tx_str("Micro Python for Teensy 3.1\r\n");
+    stdout_tx_str("Micro Python build " MICROPY_GIT_HASH " on " MICROPY_BUILD_DATE "; Teensy 3.1 version\n");
     stdout_tx_str("Type \"help()\" for more information.\r\n");
 
     vstr_t line;

unix/main.c

@@ -22,6 +22,7 @@
 #include "runtime.h"
 #include "repl.h"
 #include "gc.h"
+#include "build/py/py-version.h"
 
 #if MICROPY_USE_READLINE
 #include <readline/readline.h>
@@ -137,6 +138,9 @@ STATIC char *prompt(char *p) {
 }
 
 STATIC void do_repl(void) {
+    printf("Micro Python build " MICROPY_GIT_HASH " on " MICROPY_BUILD_DATE "; UNIX version\n");
+    printf("Type \"help()\" for more information.\n");
+
     for (;;) {
         char *line = prompt(">>> ");
         if (line == NULL) {

windows/main.c

@@ -16,6 +16,7 @@
 #include "runtime0.h"
 #include "runtime.h"
 #include "repl.h"
+#include "build/py/py-version.h"
 
 #if MICROPY_USE_READLINE
 #include <readline/readline.h>
@@ -117,6 +118,9 @@ static char *prompt(char *p) {
 }
 
 static void do_repl(void) {
+    printf("Micro Python build " MICROPY_GIT_HASH " on " MICROPY_BUILD_DATE "; Windows version\n");
+    printf("Type \"help()\" for more information.\n");
+
     for (;;) {
         char *line = prompt(">>> ");
         if (line == NULL) {