extract code regions into separate modules

[ethernian]

Code regions in Features and Adapters are quick and dirty substitutions for missing modularisation.
Let us clean up it and extract the code into appropriates modules.

https://github.com/dapplets/typescript-examples/blob/c2b6387c661cddcc32fd450288222f41fcf9d5e0/src/TwitterAdapter/index.ts#L10-L13

[ethernian]

There is a dirty hack, that needs to be fixed before this issue can be closed
dapplets/dapplet-extension#13