pub fn encode_many_config(pems: &[Pem], config: EncodeConfig) -> String {
    let line_ending = match config.line_ending {
        LineEnding::Crlf => "\r\n",
        LineEnding::Lf => "\n",
    };
    pems.iter()
        .map(|value| encode_config(value, config))
        .collect::<Vec<String>>()
        .join(line_ending)
}
Encode multiple PEM structs into a PEM-encoded data string with additional
configuration options

Same config will be used for each PEM struct.

# Example
```rust
use pem::{Pem, encode_many_config, EncodeConfig, LineEnding};

let data = vec![
Pem {
tag: String::from("FOO"),
contents: vec![1, 2, 3, 4],
},
Pem {
tag: String::from("BAR"),
contents: vec![5, 6, 7, 8],
},
];
encode_many_config(&data, EncodeConfig { line_ending: LineEnding::Lf });
```
src/pem.rs