Add links to communication changes badges to platform, storefront, all modules and channels itself

[asvishnyakov]

Currently, we support the following communication channels for our community:

• Gitter
• StackOverflow
• GitHub Issues

Add badges of this channels (and extend list of channels, if other exist) to platform, storefront and all modules readme, add links to this channels in gitter channel and stackoverflow (if possible) and issue template.

Also, up documentation links to top of readme pages