[Stale] [Telemetry] Introduce a singleton std logger to the codebase to unify logs

[derrandz]

Description

In order to achieve the goals of logging for the telemetry milestone, we will unify logging across the codebase by using a singleton logger. This logger will be imported directly in the shared scope of modules, but will also be used in the modules' scope through the telemetry module.

The origin document can be found here: #164

Changes

• Introduced the Logger interface under shared/logging
• Implemented the Logger interface while using log.Logger as the log engine and os.Stdout as the output.
• Added support for multiple log levels and a method for each level with tests

The log line format is as follows:

YYYY/DD/MM HH:MM:SS | [PREFIX] [LEVEL] : [NAMESPACE] LOG_LINE....

Example:

2022/01/08 08:29:20 | [POCKET] [INFO] : [CONSENSUS] Successfully proposed a block

Please lookup the available levels and namespaces in shared/logging/types.go

Owners

@derrandz

[Olshansk]

Going to close this out since we are unlikely to iterate on top of this PR specifically but planning on using it as a reference for when we standardize logging.