Solidity-parser Bugs

[duaraghav8]

List of (unfixed) bugs in solidity-parser

1. No support for RegExp - the literal object's value gets set to {}, eg -
   {type: "Literal", value: {}}
2. No 'name' field in StructDeclaration - this means we never get to know the name of the struct from the StructDeclaration Node object. (I've made a PR for this)
3. IsStatement malfunctioning - When using inheritance with Contract or Library, the syntax is:

contract Car is Vehicle, Engine {
        //definition
}

Solidity parser doesn't parse the 'is' section properly. the is Array's first object is fine (vehicle), but subsequent element is just a comma, not another object for Engine.

1. Exponentiation operator (double asterisk) not being parsed by solidity parser
2. A statement like uint x = 2 days; doesn't get parsed. It gives error at start of 'days'.
3. Parse of var (x) = 100; failing because x is surrounded by brackets (which is legal in solidity).