GCD Prarser and Composer

This lib helps read/write GCD files.

Reading GCD Files

```rust use std::env; use std::fs::File; use gcdrs::parser::Parser; use gcdrs::Record;

fn main() { //open the gcd file let file = File::open("in_file.gcd").unwrap();

//parser
let mut parser: Parser<File> = Parser::new(file).unwrap();

loop {
    //read and print the record until the End is received
    let record = parser.read_record().expect("Unable to read record");
    println!("Record {}", record);
    if let Record::End = record {
        break;
    }
}

} ```

Writing GCD File

```rust use gcdrs::composer::Composer; use gcdrs::record::text::TextRecord; use gcd_rs::Record; use std::env; use std::fs::File;

fn main() { //create the gcd file let file = File::create("out_file.gcd").unwrap();

//composer
let mut composer: Composer<File> = Composer::new(file).unwrap();

//write a text record
composer
    .write_record(&Record::Text(TextRecord::Simple(
        "Sample File".to_string(),
    )))
    .unwrap();
//write the end record
composer.write_record(&Record::End).unwrap();

}

```