Docs (#196)

Updated docs for LNURL pay, LNURL withdraw and Offline shop

Co-authored-by: Tiago Vasconcelos <tvasconcelos@gmail.com>

lnbits/extensions/withdraw/README.md

@@ -1,14 +1,46 @@
 # LNURLw
-## Withdraw link maker
-LNURL withdraw is a very powerful tool and should not have his use limited to just faucet applications. With LNURL withdraw, you have the ability to give someone the right to spend a range, once or multiple times. This functionality has not existed in money before.
-https://github.com/btcontract/lnurl-rfc/blob/master/spec.md#3-lnurl-withdraw
 
-With this extension to can create/edit LNURL withdraws, set a min/max amount, set time (useful for subscription services)
+## Create a static QR code people can use to withdraw funds from a Lightning Network wallet
 
-![lnurl](https://i.imgur.com/qHi7ExL.png)
+LNURL is a range of lightning-network standards that allow us to use lightning-network differently. An LNURL withdraw is the permission for someone to pull a certain amount of funds from a lightning wallet.
 
+The most common use case for an LNURL withdraw is a faucet, although it is a very powerful technology, with much further reaching implications. For example, an LNURL withdraw could be minted to pay for a subscription service. Or you can have a LNURLw as an offline Lightning wallet (a pre paid "card"), you use to pay for something without having to even reach your smartphone.
 
-## API endpoint - /withdraw/api/v1/lnurlmaker
-Easily fetch one-off LNURLw
+LNURL withdraw is a **very powerful tool** and should not have his use limited to just faucet applications. With LNURL withdraw, you have the ability to give someone the right to spend a range, once or multiple times. **This functionality has not existed in money before**.
 
-    curl -H "Content-type: application/json" -X POST https://YOUR-LNBITS/withdraw/api/v1/lnurlmaker -d '{"amount":"100","memo":"ATM"}' -H "X-Api-Key: YOUR-WALLET-ADMIN-KEY"
+[**Wallets supporting LNURL**](https://github.com/fiatjaf/awesome-lnurl#wallets)
+
+## Usage
+
+#### Quick Vouchers
+
+LNBits Quick Vouchers allows you to easily create a batch of LNURLw's QR codes that you can print and distribute as rewards, onboarding people into Lightning Network, gifts, etc...
+
+1. Create Quick Vouchers\
+   ![quick vouchers](https://i.imgur.com/IUfwdQz.jpg)
+   - select wallet
+   - set the amount each voucher will allow someone to withdraw
+   - set the amount of vouchers you want to create - _have in mind you need to have a balance on the wallet that supports the amount \* number of vouchers_
+2. You can now print, share, display your LNURLw links or QR codes\
+   ![lnurlw created](https://i.imgur.com/X00twiX.jpg)
+   - on details you can print the vouchers\
+     ![printable vouchers](https://i.imgur.com/2xLHbob.jpg)
+   - every printed LNURLw QR code is unique, it can only be used once
+
+#### Advanced
+
+1. Create the Advanced LNURLw\
+   ![create advanced lnurlw](https://i.imgur.com/OR0f885.jpg)
+   - set the wallet
+   - set a title for the LNURLw (it will show up in users wallet)
+   - define the minimum and maximum a user can withdraw, if you want a fixed amount set them both to an equal value
+   - set how many times can the LNURLw be scanned, if it's a one time use or it can be scanned 100 times
+   - LNBits has the "_Time between withdraws_" setting, you can define how long the LNURLw will be unavailable between scans
+   - you can set the time in _seconds, minutes or hours_
+   - the "_Use unique withdraw QR..._" reduces the chance of your LNURL withdraw being exploited and depleted by one person, by generating a new QR code every time it's scanned
+2. Print, share or display your LNURLw link or it's QR code\
+   ![lnurlw created](https://i.imgur.com/X00twiX.jpg)
+
+**LNBits bonus:** If a user doesn't have a Lightning Network wallet and scans the LNURLw QR code with their smartphone camera, or a QR scanner app, they can follow the link provided to claim their satoshis and get an instant LNBits wallet!
+
+![](https://i.imgur.com/2zZ7mi8.jpg)