concrete5/concrete5 — pull request #1788 by Remo (2014-06-04 06:53:35+00:00)
Title: fix boolean search attr method

Testcase by @mlocati:
- added a new boolean page attribute
- created three pages
- page1 without this attribute
- page2 with this attribute, unchecked
- page3 with this attribute, checked
- in the page search form (website/dashboard/sitemap/search/) I added this new attribute to the custom search
- leaving the attribute checkbox unchecked: no page is found
- checking the attribute checkbox: only page3 is found

I had to change the default value to null as 0 isn't the same as "null". To me:
- null should mean attr isn't selected
- 0 means attr is selected but not ticked
- 1 means selected and ticked