fix(apparmor): Fix qTox cache access

AppAmor denies access to qTox cache directory:
```
type=AVC msg=audit(1548508759.153:640): apparmor="DENIED"
operation="mkdir" profile="qtox" name="/home/vincas/.cache/qTox/"
pid=7802 comm="qtox" requested_mask="c" denied_mask="c" fsuid=1000
ouid=1000
```

Add rule to allow access to qTox cache directory.

security/apparmor/2.12.1/usr.bin.qtox

@@ -85,6 +85,7 @@ profile qtox /usr{,/local}/bin/qtox {
   owner /{,var/}run/user/[0-9]*[0-9]/qTox*.slave-socket rwl -> /{,var/}run/user/[0-9]*[0-9]/#[0-9]*[0-9], # file dialog
   owner @{HOME}/.cache/Tox/ w,
   owner @{HOME}/.cache/Tox/qTox/{,**} rw,
+  owner @{HOME}/.cache/qTox/{,**} rw,
   owner @{HOME}/.cache/thumbnails/** rw, # receiving image file produces thumbnail?
   owner @{HOME}/.config/menus/ r, # file dialog
   owner @{HOME}/.config/menus/applications-merged/ r, # file dialog

security/apparmor/2.13.2/usr.bin.qtox

@@ -91,6 +91,7 @@ profile qtox /usr{,/local}/bin/qtox {
   owner /{,var/}run/user/@{uid}/qTox*.slave-socket rwl -> /{,var/}run/user/@{uid}/#[0-9]*[0-9], # file dialog
   owner @{HOME}/.cache/Tox/ w,
   owner @{HOME}/.cache/Tox/qTox/{,**} rw,
+  owner @{HOME}/.cache/qTox/{,**} rw,
   owner @{HOME}/.cache/thumbnails/** rw, # receiving image file produces thumbnail?
   owner @{HOME}/.config/menus/ r, # file dialog
   owner @{HOME}/.config/menus/applications-merged/ r, # file dialog