Closes #35

Apply suggestion to src/Helpers/TimeAndDate.cpp

Add MessageParser tests

Apply suggestion to src/MessageParser.cpp

Fix documentation typo

Closes #19

This reduces the size of the code from 208608 to 208072 bytes, which is
totally negligible

Update documentation for the ECSS definitions

Group Services and ECSS Definitions into a doxygen page

Use a non-templated version of etl::string

Set the etl format as a static variable for the Logger

This prevents wasting time recreating the format variable every time the
LOG function is called.

Force inlining the LOG function

This forces the compiler to check the `if constexpr` structure, and
disable the logging line entirely if needed.

Never redefine the log level

Move `disabled` logging level to ease level checks

Thanks @xlxs41 for the suggestion!

Reinstantiate log level checks

Fix documentation, as suggested by @thodkatz

Add a few more documentation lines to LogEntry

Fixes for cppcheck-misra and vera checks due to updates & false positives

Apply suggestion to inc/Logger.hpp

Be explicit about the type used in the LogLevel enumeration

This makes LogLevel an unscoped strongly-type enumeration, making sure
there is consistency between the expected log level of uint8_t

Fix a bug with error names not showing up in the logs

Take care of MISRA and vera++ concerns