APK generated app's colour change

[opticod]

Inspired by #402 , we can extend the colour change to generated APKs also...We will be having these colours accordingly:

<color name="colorPrimary">#</color>
<color name="colorPrimaryDark">#</color>
<color name="colorAccent">#</color>
<color name="white_primary_text">#</color>
<color name="white_secondary_text">#</color>
<color name="black_secondary_text">#</color>

Need to make these changes for simulator and generated APKs....changes for generated APKs should be directed to https://github.com/BuildmLearn/Toolkit-mobile-templates

[croozeus]

Thanks for initiating this @opticod