Macro putHex 

macro_rules! putHex {
    ($val:ident,$key:ident,$typ:ident,$slf:ident.$($x:ident).+) => { ... };
}

Parse a hex string containing multiple bytes and put value into the image using the given key path.

putHex!(val:&str,key_path:&Vec<String>,image_type:String,self.path.to.bytes:[u8])