chore(base-cluster/docs): add info about fix versions

set modeline

charts/base-cluster/README.md.gotmpl

@@ -1,3 +1,4 @@
+<!-- vim: set ft=markdown: -->
 {{- $majorVersion := index ((.Files.Get "Chart.yaml" | fromYaml).version | split ".") "_0" -}}
 {{- $fluxMajorVersion := "2" -}}
 
@@ -14,7 +15,7 @@
 
 ## Cluster bootstrap
 
-The `.x.x` part of the versions can be left as is, helm uses that as a range.
+The `.x.x` part of the versions can be left as is, helm uses that as a range. If you choose to set a fix version, you have to take care of the updates yourself.
 
 ```sh
 # always be git 😁
@@ -87,7 +88,7 @@ so the kube-scheduler can, hopefully, schedule them on nodes with more space.
 Additionally, the descheduler also tries to reconcile `topologySpreadConstraints`
 and affinities.
 
-If the cluster is _semi_ underspecced or the individual applications have unperfect
+If the cluster is _semi_ underspecced or the individual applications have imperfect
 resource requests, the descheduler might lead to period restarting of random pods.
 
 In that case you should disable the descheduler.