Remove FW_ARRAY_TO_STRING #375

[jwest115]

• Updated array cpp codegen to use FW_SERIALIZABLE_TO_STRING instead of FW_ARRAY_TO_STRING
• Removed || FW_ENABLE_TEXT_LOGGING in enum code gen. Per the static assertions in the F Prime config, if text logging is on, then serializable strings are on. See https://github.com/nasa/fprime/blob/af76f089e5aaee774d129e9005e19aaeab36e2f0/Fw/Cfg/ConfigCheck.cpp#L39-L42.
• Regenerated fpp-to-cpp test reference files
• Updated examples in the User's Guide and removed outdated code.

Closes #375.