Add support for T-Digest (#2214)

* wip

* close #2216 - add support for TDIGEST.MERGESTORE and make compression optional on TDIGEST.CREATE

* fix some tdigest commands, use bloom edge docker

* fix index.ts

* 2.4-RC2 (v2.4.1)

* fix some commands and tests

* clean code

packages/bloom/lib/commands/t-digest/CREATE.spec.ts

@@ -0,0 +1,30 @@
+import { strict as assert } from 'assert';
+import testUtils, { GLOBAL } from '../../test-utils';
+import { transformArguments } from './CREATE';
+
+describe('TDIGEST.CREATE', () => {
+    describe('transformArguments', () => {
+        it('without options', () => {
+            assert.deepEqual(
+                transformArguments('key'),
+                ['TDIGEST.CREATE', 'key']
+            );
+        });
+
+        it('with COMPRESSION', () => {
+            assert.deepEqual(
+                transformArguments('key', {
+                    COMPRESSION: 100
+                }),
+                ['TDIGEST.CREATE', 'key', 'COMPRESSION', '100']
+            );
+        });
+    });
+
+    testUtils.testWithClient('client.tDigest.create', async client => {
+        assert.equal(
+            await client.tDigest.create('key'),
+            'OK'
+        );
+    }, GLOBAL.SERVERS.OPEN);
+});