When creating new batch, provide default org

[JoeMurray]

If a batch is created without filling in options, Company is left as 'Any'. When trying to add Contribution to batch, this causes an error as owner of financial account for payment method doesn't match that of null value for batch.

1. Create default for Company as contact_id of first enabled financial account.
2. Change validation when adding a contribution to a batch on all backend forms so that there is no error on payment method not matching organization of batch if the latter is any.
3. Change label and name of field from Company to Organization.

[JoeMurray]

On 2, add test for !empty($ownerID) after https://github.com/JMAConsulting/biz.jmaconsulting.easybatch/blob/master/CRM/EasyBatch/BAO/EasyBatch.php#L441

[JoeMurray]

On 1, add default at https://github.com/JMAConsulting/biz.jmaconsulting.easybatch/blob/master/easybatch.php#L250

[JoeMurray]

Completed 3 at 65d3fe1

[JoeMurray]

Actually, 3 required additional changes at ee2c6bf and 83c223d but these involved renaming Company to Organization for label, variable and html. The variable change (likely) cause the contents of the Company column to be displayed as undefined.