Add utf8 bom for ms excel

[itcrab]

Hi, Jonathan!

In one of my project I have a problem with cyrillic symbols in generated CSV-file.

We have simple source:

require_once __DIR__ . '/vendor/autoload.php';

$writer = new \EasyCSV\Writer('write.csv');
$writer->writeFromArray(array(
    'колонка 1, колонка 2, колонка 3',
    array('значение 1', 'значение 2', 'значение 3')
));

And when we open it CSV-file in MS Excel take this:

For solve this problem I do this PR. Now you may set flag $isNeedBOM for give know Writer to insert UTF-8 BOM symbol in start CSV-file. When you do reading this CSV-file we checks exists UTF-8 BOM symbol and if it true - remove from first line.

Some source:

$writer = new \EasyCSV\Writer('write.csv', 'r+', true);
$writer->writeFromArray(array(
    'колонка 1, колонка 2, колонка 3',
    array('значение 1', 'значение 2', 'значение 3')
));

Give us good result on MS Excel:

I add small tests for this PR and if you see any more tests I will be add its.

[itcrab]

@jwage ping

[sharipoutra5]

I agree and I want to learn more

[itcrab]

@jwage ping

[itcrab]

@jwage ping

[simwodb1]

good

[itcrab]

@jwage ping

[itcrab]

@jwage you may merge my pull request?

[jwage]

👍 sorry for the delay.

[hussain2022a]

Hussain @ #