Hack the max-number-of-files-message to consider window.maxFileUploads

[jcatrysse]

Added a fix to have the max-number-of-files-message consider window.maxFileUploads

Reference: https://www.redmine.org/issues/18555

This, however, does not entirely resolve the issue because the message will always state the max_number_of_files = 10.

In: app/views/attachments/_form.html.erb

:max_number_of_files => (multiple ? 10 : 1)

should be:

:max_number_of_files => (multiple ? Setting.plugin_that_attachments_limit['attachments_limit'].to_i : 1)

I'm not confident how to change that in an orderly fashion.