Add missing copyright blurbs
Clarify that files by default are GPLv3.
Fix wording in info message.

edit.maxfilesize is an internal detail that has no meaning to
the user, and it makes for broken grammar.
Merge pull request #2000 from dottedmag/master

Add missing copyright blurbs
Respect max_file_size set to 0 to mean "unlimited"

As documented, an explicitly set value of 0 should mean "any size".

Also, consistently initialize the value to 100K, as documented.

See Redmine 6588
Merge pull request #2001 from vohi/redmine/6588

Redmine/6588