Fix error when internal link has space.

e.g. ammo link in weapon description and vice versa

Bug is serious, has to release a fix.
Cherry pick cleanup and enhancements.

Picked from commit fb92572b888cc618bcc88a11863fc45f92f7b446 and a0177a4d8c8c9932024cbc309d28d1973fbb83b4
Split item into subcat. Multi-col index. Faster data inflate.

Fixed bug when navigating to an internal link with space, which is the primary reason of release.
Improves readability of license and help page.