Sample Button on RDKB Local WebUI for DAC Support

Introduction

• Need to add one tab(DAC Demo) in left panel in landing page of RDKB WebUI(http://10.0.0.1).
• Upon clicking "DAC Demo" tab, new page should be loaded in right panel.
• New page should have a Text field and a button.
• On clicking the Execute button, the script mentioned in the text field should be executed in the running target and the result should be notified in local WebUI (perhaps through alert).

Build Procedure

             Need to flash base build as rdkb rpi3 build ,

$ mkdir <workspace dir>
$ cd <workspace dir>
$ repo init -u https://code.rdkcentral.com/r/manifests -b dunfell -m rdkb-extsrc.xml
$ repo sync -j`nproc` --no-clone-bundle

Add Dobby package in RDK-B build -  meta-cmf-raspberrypi/recipes-core/packagegroups/packagegroup-rdk-ccsp-broadband.bbappend 

+++ b/recipes-core/packagegroups/packagegroup-rdk-ccsp-broadband.bbappend
@@ -6,6 +6,9 @@ RDEPENDS_packagegroup-rdk-ccsp-broadband_append = "\
     libseshat \
     notify-comp \
     start-parodus \
+    dobby \
+    crun \
     \
 "

$ MACHINE=raspberrypi-rdk-broadband source meta-cmf-raspberrypi/setup-environment
$ bitbake rdk-generic-broadband-image