Special:Statistics: Change link target for content pages to hide redirects

Special:Statistics: Change link target for content pages to hide redirects

Content pages, as visible on Special:Statistics, doesn't include
redirects in the visible counter. But the link target (Special:AllPages)
includes redirects in the default view, which could be confusing, if a
user expects all pages excluding redirects.

Change the link target of Content pages to hide redirects by default and
add a link for "Pages" to the default view of Special:AllPages.

Change-Id: I1c1ada8e3d16d19db8315eccfbea2c753814659e