Add Buffer creation convenience

[Cyrildavids]

For some reason when i try to use this in an Angular Application it complains about fs.readFile not existing. So i resorted to using the base64 version of the image binary. I had to modify the library to accept base64 string without interfering with any of the processes that are already exists except converting base64 string to an array buffer and then on to a Buffer ready for processing.
An example usage will be
new EXIFImage({ image: this.base64Image, imageDataType: 'base64' }, function (error, exifData) { if (error) console.log('Error: ' + error.message); else { console.log(exifData); // Do something with your data! } });
or
new EXIFImage({ image: this.arrayBuffer, imageDataType: 'ArrayBuffer' }, function (error, exifData) { if (error) console.log('Error: ' + error.message); else { console.log(exifData); // Do something with your data! } });

[oeuillot]

Hello,
Why dont you use UInt8Array.from(source) ?

https://developer.mozilla.org/fr/docs/Web/JavaScript/Reference/Objets_globaux/TypedArray/from