Update iso690-numeric-en.csl

Delete ANON. for documents with no author.
Small bug fixes on some fields display.
Update iso690-numeric-en.csl
Update iso690-numeric-en.csl
Update iso690-numeric-en.csl
Update iso690-numeric-en.csl
Update iso690-numeric-en.csl
Update iso690-numeric-en.csl
Update iso690-numeric-en.csl
Merge pull request #519 from grolimur/patch-19

Update iso690-numeric-en.csl