add note in legacy readme about why it exists

Author: g-harel

README.legacy.md

@@ -1,3 +1,7 @@
+The legacy API exists to preserve compatibility for users importing the package using a `script` tag. Because [unpkg.com](https://unpkg.com) serves the latest version of the package if no version is specified, I can't break backwards compatibility, even with a major release. This API also preserves a few features that could potentially be still be useful to some users (guide rendering and editable svg).
+
+---
+
 ## Install
 
 ```ts

README.md

@@ -31,7 +31,7 @@ import * as blobs2 from "blobs/v2";
 
 ```js
 const svgPath = blobs2.svg({
-    seed: Date.now(),
+    seed: Math.random(),
     extraPoints: 8,
     randomness: 4,
     size: 256,
@@ -44,7 +44,7 @@ doSomething(svgPath);
 ```js
 const svgString = blobs2.svg(
     {
-        seed: Date.now(),
+        seed: Math.random(),
         extraPoints: 8,
         randomness: 4,
         size: 256,
@@ -63,7 +63,7 @@ container.innerHTML = svgString;
 ```js
 const path = blobs2.canvasPath(
     {
-        seed: Date.now(),
+        seed: Math.random(),
         extraPoints: 16,
         randomness: 2,
         size: 128,
@@ -81,7 +81,7 @@ ctx.stroke(path);
 ```ts
 export interface BlobOptions {
     // A given seed will always produce the same blob.
-    // Use `Date.now()` for pseudorandom behavior.
+    // Use `Math.random()` for pseudorandom behavior.
     seed: string | number;
     // Actual number of points will be `3 + extraPoints`.
     extraPoints: number;