RFC : Better searches on orders

This RFC would enhance acqui/histsearch.pl

One could reuse the filters for statistics as defined in RFC Improving statistics on acquisitions.

Id est:

• order date: beginning; end
• reception date: beginning; end
• library branch
• vendor
• librarian
• budget
• budget's authorized value #1
• budget's authorized value #2

These would be added to the existing search options (Title, Author, Vendor).