Trace reports - exchange-specific tracing; proof exchange tracing

[ianco]

Still a few outstanding TODO's, but opening up the PR to get some eyes on it.

Adds exchange-specific tracing (adds a "trace" attribute to the exchange records as well as admin API inputs and outputs).

Added tracing to proof exchange and credential exchange.

Added support to the alice/faber demo to support tracing to standard log and http endpoint.

TODO:

• append trace logs to messages is partially implemented - need to either finish this or rip out the code
• had to add reference to the EFK docker network into the test and demo scripts - need to clean this up - FIXED
• also need to look into the implications for message forwarding and routing ...
• anything else from the reviews ...

[lgtm-com]

This pull request introduces 1 alert when merging 79f3254 into caf4572 - view on LGTM.com

new alerts:

• 1 for __eq__ not overridden when adding attributes

[ianco]

This pull request introduces 1 alert when merging 79f3254 into caf4572 - view on LGTM.com

new alerts:

• 1 for eq not overridden when adding attributes

Fixed

[codecov-io]

Codecov Report

Merging #451 into master will decrease coverage by 0.04%.
The diff coverage is 83.45%.

@@            Coverage Diff             @@
##           master     #451      +/-   ##
==========================================
- Coverage   90.60%   90.55%   -0.05%     
==========================================
  Files         248      249       +1     
  Lines       12216    12455     +239     
==========================================
+ Hits        11068    11279     +211     
- Misses       1148     1176      +28     

[ianco]

Will likely have further changes but I'd like to get this PR merged and into a release (even a beta release) so we can get this deployed/tested on OpenShift