feat(supported-version): dynamically compute (#120)

Previously, I maintained supported versions by revising a file of versions. This was monotonous, like time.

Now, these are just based upon the documented EoL dates of the versions published by Magento.

supported-version/src/kind/get-currently-supported.ts

@@ -0,0 +1,7 @@
+import { MagentoMatrixVersion } from '../matrix/matrix-type';
+import allVersions from '../versions/individual.json';
+
+export const getCurrentlySupportedVersions = (date: Date): string[] => 
+        Object.entries(<Record<string,MagentoMatrixVersion>>allVersions)
+                .filter(([key, value]) => new Date(value.eol) >= date)
+                .map(([key, value]) => key);