Added ommitted folders that need chmod for installation

when installing opencart, some folders mentioned in install.txt do not exist yet. the installer than lists some more folders than are contained in install.txt to be chmod'ed.
Fix tag search
Merge pull request #843 from josephok/v1.5.6

Fix tag search
Merge pull request #837 from kstenschke/patch-1

Added ommitted folders that need chmod for installation
Fixed SQL typo and added missing quote mark in setting model / update setting value method.