Feature/custom branding

[alexteusz]

the following Settings were added that must be edited in the Embedding Code of a website the Webchat should be displayed on: 

 

enableCustomBranding	boolean	false				If true, shows a custom branding instead of the standard one
customBrandingTitle	string	""				The title of the custom branding, such as "Please find our Privacy Policy here"
customBrandingURL	string	""				The optional URL that will be opened when a user clicks on the custom branding title.