Enforcing PEP8 - Indents fixed
Enforcing PEP8 - Docstrings fixed
Enforcing PEP8 - Changed names of variables that shadowed builtins
Code refactoring - defaultlist

Since list is a class we should use a super notation to use base methods in descendants. Also set_len may be considered as an internal method so add an underscore suffix to stress the fact that it shouldn't be considered as a public method.
Enforcing super usage for calling base methods' implementations.
Eliminating magic - less magic fields/methods used leads to cleaner code. Appropriate builtins should be used instead.
Tests refactoring - enforcing pythonic names for variables. Using underscores as words separator.
Tests refactoring - simplified string formatting and removed side effects of assertMessage in utils module
Code refactoring - Bootstrap. Improved peers rotation logic since original implementation was extremely unefficient.

Since peers stored as a field used only by Bootstrap added underscore suffix to field name to stress the fact that it is an internal field (not designed to be used from outside).
Code refactoring - Bootstrap. Renamed class members to distinguish between 'public' and 'non-public' members
Enforcing PEP8 - Renamed 'viewid' to 'view_id' globally
Code refactoring - renamed 'cid' to 'client_id' globally.

Short names and abbreviations aren't good even if they're widely used in standard description.
Code refactoring - Acceptor. Renamed class members to distinguish between 'public' and 'non-public' members.
Code refactoring - Request. Renamed class members to distinguish between 'public' and 'non-public' members. Also changed some field names to include some semantic meaning.
Code refactoring - Request. Renamed class members to distinguish between 'public' and 'non-public' members. Also changed some field names to include some semantic meaning.

Added some TODOs.
Code refactoring - Commander. Renamed class members to distinguish between 'public' and 'non-public' members.
Code refactoring - deterministic_network.py. Little code optimizations.
Code refactoring - Heartbeat. Renamed class members to distinguish between 'public' and 'non-public' members.
Code refactoring - Leader. Fixed comments
Code refactoring - Leader.

* Added issues list
* Removed defaultlist usages (replaced with dict)
* Added TODOs