Remove static Token EndOfFile

[fm-117]

In Token.cs at line 417:

TypeCobol/TypeCobol/Compiler/Scanner/Token.cs

Line 417 in 8312290

public static Token END_OF_FILE = new Token(TokenType.EndOfFile, 0, -1, TypeCobol.Compiler.Scanner.TokensLine.CreateVirtualLineForInsertedToken(-1, String.Empty));

A Token instance should not be shared amongst several documents, each source file must get its own end-of-file token.
Besides, depending on how the token is used, it may retain large amount of data through its TokenSource and this could cause memory leaks.

• Track every usage of the shared token and update accordingly
  • compare to TokenType.EndOfFile instead of comparing to the instance
  • create a new instance when needed