A few functions just take a pointer to the input class as arguments. Lets make them member functions.
Continue converting functions to methods.
Move printing of options to a member function.

The old function called convertZToSymbol() so I have added 2 new
members for Z{min,max}Symbol that are set where appropriate in the
code and used in this new member function.
Move checking of input file values function to a member.

Also move definition of MAX and MIN values of N&Z to the same class
as the values are actually stored.
Remove function declarations that are no longer used.
Move Z->Symbol, Symbol->Z and setExtreme() functions to members.

Have also got rid of the symbol member of the Nuclide class as I
could not see a way to make it work once the conversions moved to
member functions, and this was the only time it was used. The
conversion to symbol is now called on demand as we write the
output file.

The conversion functions are bascially big maps so have been put
in their own files to avoid polluting the other functions of the
inputs class. They should probably be members of Nuclide or free
floating for global use, however they are currently only used
when dealing with the inputs class which is why I have put them in
there.
Use a ternary operator.
Use a more consistent name for this function.
Use a more descriptive function name.
Use a more consistent function name.
More naming alterations in an attempt to provide consistency across the project.
Correct logic error involving isotopes without isomers and those in user list.

Also move to ternary operator for some conditions.
Move setCanvasSize() from free method to member function.
Construct the full R-process file name with the rest of the files.
Merge branch 'Methods'

Many functions only took a pointer to the inputs class as an argument
so convert them to member functions.

Change a few other function names to bring more consistency to the
project as a whole.