docs: Update republish time and lightly reorganize republish info (#48)

PR-URL: #48
Credit: @neverett
Reviewed-By: @zkat

doc/cli/npm-unpublish.md

@@ -24,14 +24,15 @@ If no version is specified, or if all versions are removed then
 the root package entry is removed from the registry entirely.
 
 Even if a package version is unpublished, that specific name and
-version combination can never be reused.  In order to publish the
-package again, a new version number must be used.
+version combination can never be reused. In order to publish the
+package again, a new version number must be used. Additionally,
+new versions of packages with every version unpublished may not
+be republished until 24 hours have passed.
 
 With the default registry (`registry.npmjs.org`), unpublish is
-only allowed with versions published in the last 72 hours.  Similarly,
-new versions of unpublished packages may not be republished until 72 hours
-have passed. If you are trying to unpublish a version published longer
-ago than that, contact support@npmjs.com.
+only allowed with versions published in the last 72 hours. If you
+are trying to unpublish a version published longer ago than that,
+contact support@npmjs.com.
 
 The scope is optional and follows the usual rules for `npm-scope(7)`.