nsh scripting:source (.) cmd supported

Tools/px4airframes/rcout.py

@@ -74,7 +74,7 @@ class RCOutput():
         result += "\n"
         result += "if [ ${AIRFRAME} != none ]\n"
         result += "then\n"
-        result += "\tsh /etc/init.d/airframes/${AIRFRAME}\n"
+        result += "\t. /etc/init.d/airframes/${AIRFRAME}\n"
         if not post_start:
             result += "else\n"
             result += "\techo \"ERROR  [init] No file matches SYS_AUTOSTART value found in : /etc/init.d/airframes\"\n"

Tools/serial/rc.serial.jinja

@@ -11,7 +11,7 @@ set PRT {{ command.port_param_name }}
 set i {{ command.instance }}
 {% endif -%}
 # get the device & baudrate
-sh $PRT_F
+. $PRT_F
 if [ $SERIAL_DEV != none ]; then
 {% if not constrained_flash -%}
 	echo "Starting {{ command.label }} on $SERIAL_DEV"