[IMP] account_invoice_entry_date v8 porting
[FIX] readme
[FIX] description
[FIX] redundant backslash
[FIX] multiline string formatting
[FIX] missing space
[FIX] pep8
Merge pull request #61 from abstract-open-solutions/8.0-reg-date

[ADD] [8.0] account_invoice_entry_date