Batch sending data on big filesystems

[DavertMik]

Use the same policy we have with lagre XMLs
Split tests by size/files
Send data in batches

testomatio/app#1599

[AenEnlil]

Add next parameters to request:

• chunk_upload. true/false. Used to identify kind of import
• finish. true/false. Send true with last chunk, so we could finish import
• import_id. You will receive it after first chunk uploaded

[DenysKuchma]

@AenEnlil Test after implement BE or tag me for test
#265