Ugly error lists when multiple errors are present on a sample sheet validation

[JeffreyThiessen]

Errors should be human readable, currently the whole array is written to string, [ and ] included.

[JeffreyThiessen]

Because we are using the ugly errors as the base for what we write to the status file they can look really ugly sometimes.

ex:

{
    "Date Time": "2019-05-16 14:47",
    "Message": "ERROR! Could not initialize irida api. Errors: ('Could not get access token from IRIDA. Credentials may be incorrect. IRIDA '\n \"returned with error message: ('Decoder failed to handle access_token with \"\n 'data as returned by provider. A different decoder may be needed. Provider '\n 'returned: b\\\\\\'{\"error\":\"invalid_client\",\"error_description\":\"Bad client '\n 'credentials\"}\\\\\\'\\',)',)",
    "Upload Status": "error"
}

[JeffreyThiessen]

Since we are storing json we should just change to the object to include an errors list. Then when pretty printed it will look cleaner automatically.