Improve & refactor interactive tutorial code

Interactive tutorials: more consistent style

Interactive tutorials: Use new generics for send-xrp, use-tickets

Interactive tutorials: clean up now-unused code

Interactive tutorials: progress & debugging of errors

Interactive: Require Destination Tags; and related

- Validate addresses in Transaction Sender and warn on Mainnet X-address
- Option to load destination address from query param in Tx Sender
- Some more/updated helpers in interactive tutorial JS

Interactive tutorials: fix JA version

Interactive tutorials: readme, include code filter (incomplete)

Interactive tutorials: improvements for consistency

Interactive Tutorials: finish readme

Interactive tutorials: fix syntax errors

content/_snippets/interactive-tutorials/connect-step.md

@@ -0,0 +1,17 @@
+{% if use_network is undefined or use_network == "Testnet" %}
+  {% set ws_url = "wss://s.altnet.rippletest.net:51233" %}
+  {% set use_network = "Testnet" %}
+{% elif use_network == "Devnet" %}
+  {% set ws_url = "wss://s.devnet.rippletest.net:51233" %}
+{% elif use_network == "Mainnet" %}
+  {% set ws_url = "wss://xrplcluster.com" %}
+{% endif %}
+
+{{ start_step("Connect") }}
+<button id="connect-button" class="btn btn-primary" data-wsurl="{{ws_url}}">Connect to {{use_network}}</button>
+<div>
+  <strong>Connection status:</strong>
+  <span id="connection-status">Not connected</span>
+  <div class="loader collapse" id="loader-connect"><img class="throbber" src="assets/img/xrp-loader-96.png"></div>
+</div>
+{{ end_step() }}