Better file structure and organization

[E3V3A]

Implement a more organized and logical file structure.
Now we have the following directories:

 .git
 assets        // where we keep: config.txt (template), private API keys etc  
 docs          // where we keep GitHub related docs
 images        // where we keep GitHub related images
 node_modules 
 resources     // where we keep personal or universal voice models and sound files 
 scripts       // where we keep the google-authentication scripts
 translations 

We would like to:

• keep all API keys, secrets and related files in one directory assets
• keep all voice models (MMM default, universal, personal) in a resources subdirectory:
  • p_models
  • u_models
  • alexa
  • ga