Support full scope of valid characters allowed in property names

[safris]

RFC 8259 states there are no limits imposed on the value of strings used as JSON object names.

An object structure is represented as a pair of curly brackets surrounding zero or more name/value pairs (or members). A name is a string. A single colon comes after each name, separating the name from the value. A single comma separates a value from a following name. The names within an object SHOULD be unique.

object = begin-object [ member *( value-separator member ) ]
         end-object

member = string name-separator value

ECMA-262 explicitly states that all strings are valid object property names.

A property key value is either an ECMAScript String value or a Symbol value. All String and Symbol values, including the empty String, are valid as property keys. A property name is a property key that is a String value.

RFC 8259 lists the characters that must be escaped in JSON:

All Unicode characters may be placed within the quotation marks, except for the characters that MUST be escaped: quotation mark, reverse solidus, and the control characters (U+0000 through U+001F).

ECMA-262 lists the characters that must be escaped in JavaScript:

A string literal is 0 or more Unicode code points enclosed in single or double quotes. […] All code points may appear literally in a string literal except for the closing quote code points, U+005C (REVERSE SOLIDUS), U+000D (CARRIAGE RETURN), and U+000A (LINE FEED).