Create five additional namespaces for pflwiki

Per the model of alswiki.
The community specifically requested "Dischbediere" to be used here. It
is inconsistent, but the dropdown at [[pfl:Special:AllPages]] confirms
that "Dischbediere" is used on almost all talk namespaces.

Bug: 52671
Change-Id: Iffc14000eb425d4d43f3a2fae42910b2c5cba3d8