Feat/explicit conversion operator

Fix unused parameter

wrap implicit conversions tests around the JSON_USE_IMPLICIT_CONVERSIONS
macro

Merge Gitlab actions

Serialisation macros: increase upper bound on number of member variables

[JSON] initialise all member variables. Maybe this will shut valgrind up. std::tie probably wasn't the problem initially

fix eof for get_binary and get_string

[JSON] since we no longer use a netbeans project for the (de)serialisation macro building code, can revert the changes made to the .gitignore file

[JSON] rough and ready code for generating (de)serialisation macros. Current upper bound on number of member variables is set to 64

[JSON] 	- dirty code for building intrusive and non-intrusive serialisation/deserialisation macros for custom types
		- updated .gitignore file to ignore private netbeans project configurations

[JSON] 	- dirty code for building intrusive and non-intrusive serialisation/deserialisation macros for custom types
		- used code to increase the upper bound on number of member variables to 64

[JSON] 	- dirty code for building intrusive and non-intrusive serialisation/deserialisation macros for custom types
		- used code to increase the upper bound on number of member variables to 64

[JSON] 	- dirty code for building intrusive and non-intrusive serialisation/deserialisation macros for custom types
		- updated .gitignore file to ignore "dist" and "build" directories in netbeans project 

[JSON] 	- dirty code for building intrusive and non-intrusive serialisation/deserialisation macros for custom types
		- netbeans project configurations

[JSON] dirty code for building intrusive and non-intrusive serialisation/deserialisation macros for custom types

Add static assertion for missing binary function in SAX interface

add inline specifier for detail::combine