0.1.2

- DONE Use an intermediary server between org and trello to permit asynchronous actions
- DONE Change org-trello's loading policy + update the readme about it
- DONE Find a way to make the proxy less verbose
- DONE Fix the loss of todo keywords after the synchronization -> no idea what's wrong here
- DONE Improve the attachment board routine to add the missing | keyword (hardcode with DONE for example)
- DONE Improve the clearing of already present heading metadata
- DONE Improve the help message to categorize the bindings
- DONE Improve the starting/stopping of org-trello
- DONE Remove end to end test as this can no longer works with asynchronous
- DONE Update the readme to explain the migration from 0.1.1 to 0.1.2
- DONE Render the sync to trello routine asynchronous
- DONE Render the sync complex entity routine asynchronous
- DONE Render the sync from trello asynchronous
- DONE Fix check setup routine
- DONE Interactive command to cleanup the org-trello data from the current buffer
- DONE Interactive command to delete all entities from the board and the org buffer
- DONE Update version
- DONE Release notes
- DONE Release