…ace to satisfy ADL requirements.

- LogLevel is now a top level enum class.
- Added a new log level Off to disable output from a specific module.
- Logger::LogLevel is a deprecated alias to LogLevel.
- Logger::Info, Debug, Error are deprecated aliases to LogLevel::...
- Removed public "internal*" functions from Logger.Logger
- Added LogSource struct to encapsulate source information.
- Added shouldLog method to check if a log should be emitted for a given level and module.
- Removed nonfunctional artifacts "m_LogStream" and "Logger::operator<<"
- Added templated "log" functions that are friends to Logger.
- Reworked PCPP_LOG macros to no longer utilize the now removed internal functions.
- Added PCPP_LOG_INFO macro level.
- Changed PCPP_LOG_ERROR to now check if the log should be emitted.
- Fixed NetworkUtils log module name overlapping with NetworkUtils class.
- Fixed missing enum value for PacketLogModuleSll2Layer.

This reverts commit be95ab8.

- Added optional compile time elimination of log calls below set level.

- Renamed printLogMessage to emit and changed visibility to public.
- Added new class LogContext to encapsulate a single emittable log message.
- Added new methods createLogContext which is practically a rework of internalCreateLogStream but returns a LogContext.
- Added optional use of object pooling optimization for reusing log contexts. (Enabled via preprocessor flag PCPP_LOG_USE_OBJECT_POOL)

… minimum log level set to too high severity..

…ntext pooling.

- Removed preprocessor variable PCPP_LOG_USE_OBJECT_POOL.
- Disabled context pooling for the unit tests as it interferes with the memory leak checker.

… time minimum log level set to too high severity..

- Added documentation to new methods and classes.
- Addressed explicit constructor warnings.
- Moved disable of context pooling for unit tests to the main.cpp files of the respective tests.

- Added 2 preallocated log contexts to the object pool.

…hreading and eliminate possibility of data races during log emission.