fix: add default for cid base and fix cid version override

Author: achingbrain

src/cli/commands/add.js

@@ -85,7 +85,8 @@ module.exports = {
     'cid-base': {
       describe: 'Number base to display CIDs in.',
       type: 'string',
-      choices: multibase.names
+      choices: multibase.names,
+      default: 'base58btc'
     },
     hash: {
       type: 'string',

src/core/components/add/index.js

@@ -18,7 +18,7 @@ module.exports = ({ ipld, gcLock, preload, pin, options: constructorOptions }) =
     }
 
     // CID v0 is for multihashes encoded with sha2-256
-    if (opts.hashAlg && opts.cidVersion !== 1) {
+    if (opts.hashAlg && opts.hashAlg !== 'sha2-256' && opts.cidVersion !== 1) {
       opts.cidVersion = 1
     }