Fix reciprocal minor tick spacing; bump to 0.84

Minor ticks on 1/x scales were using linear value interpolation between
harmonically-spaced major ticks. Because 1/v is highly convex, equal value
steps near a large major-value (left side of the first interval) map to tiny
physical steps, piling all ticks against the left wall. At a 1:1000 ratio the
first four minor ticks land at 0%/0%/1%/2% of the interval.

Fix: interpolate in position space (uniform physical spacing) for all
reciprocal intervals, matching how major ticks are laid out (also equal
physical steps) and matching the already-correct ∞-first-interval handling.

Also documents 1/x scale and ∞ max in README.

k8s/deployment.yaml

@@ -15,7 +15,7 @@ spec:
     spec:
       containers:
         - name: m1730-generator
-          image: git.baumann.gr/adebaumann/m1730-generator:0.83
+          image: git.baumann.gr/adebaumann/m1730-generator:0.84
           imagePullPolicy: Always
           ports:
             - containerPort: 5000