Add: add neo smart contract syntax analyzer

[Jim8y]

This pr adds the syntax rules of the neo smart contract.

It:

• Bans the use of decimal type
• Bans the use of double type
• Bans unsupported BigInteger, String, Char, Math methods and syntax.
• Bans out, ref keywords.
• Bans the use of LINQ.
• Bans unsupported collection types.

All baned syntax will show errors in the IDE.

Code Fix:

double => long;
float => int;
out => local variable and return value;
anonymous function => methods;

[Jim8y]

[Jim8y]

Will add syntax analyer for using using BigInteger = System.Numerics.BigInteger;

[Jim8y]

Add syntax check for UInt160 and ECPoint assignment format check

[shargon]

UTs

[Jim8y]

@shargon now good to go.

[shargon]

How can we use this analyser in the smart contract?

[Jim8y]

@shargon now use this analyer in the examples to demonstrate how to use it.

[shargon]

Thanks @Jim8y, now is ready for me