[c] Fix unregister command

Closes #22

See merge request !94

[p] Try to fix hanged rooms

Closes #23

See merge request !93

Unifomrizing imports

Closes #14

See merge request !92

[t][c] Add recover procedure

- Creation of a recovery file in case of client crash during signing
- Recovering call to TTP from recovery file
- Persisting the resulting contract if possible

See merge request !91

[p] Improve mail templates

- Add contract UUID
- Fix typos

See merge request !90

- Add contract UUID
- Fix typos

[p] Fix ready sign timeout

Closes #15

See merge request !89

[p][c] Unregister user

- Add `unregister` command to the client
- Handle `UnregisterRequest` plateform-side

See merge request !85

[p] Handle case in mails

Closes #12

See merge request !86

[demo] Verbose flag print DLog to stdout

Should fix #13

See merge request !88

[p] Change default ttp port during ttp command

Closes #11

See merge request !87

[d] Net is now blocking



See merge request !84

[d] Add servers event (platform and TTP)



See merge request !83

Add mutex on ttp

Prevent the problems due to concurrent access to the ttp

See merge request !82

397 signature timeout



See merge request !81

218 promesses client



See merge request !80

This huge commit adds the following features:

- Change default timeout to 5 sec (to be updated soon)
- Don't send TTP information in contract file, but during start signal
- Platform: load and save TTP data from a local file
  New flags: --addr and --ttps
- Platform ttp command: automatically save ttp data in the local file
  (addr and certificate hash are the only values needed by the platform
  and the clients)
- Update integration tests to integrate TTP