Improved array support
Added support for arrays of strings.
Removed explicit use of start().  All calls implicitly initialize
the Julia engine if it is not already initialized.
Added support for returning Arrays of strings as well as implicit
conversion from Array of SubString to Array of String.
Fixed linkage of function template arguments to satisfy gcc.
Additionally support implicit conversion of primitive Substring to String
More gcc template stuff.
Support for null as primitives and as array elements.
Support for Julia version dependent Void type use.
Added return style to eval, exec and script.exec for both node 10
and node 11 implementations.
README++
README++
README++
package++
package++