update readme

README.md

@@ -8,5 +8,22 @@ Flarum is down - read as Markdown
 
 CLI tool for Flarum v2 that allows to export public DB into Markdown format.
 
-> [!IMPORTANT]
-> In development
+## Install
+
+``` bash
+cargo install flarumdown
+```
+
+## Usage
+
+``` bash
+RUST_LOG=warn flarumdown -s '/path/to/flarum.sqlite' \
+                         -t '/path/to/target' \
+                         -u '/path/to/flarum/public' \
+                         -i index \
+                         -r http://[202:68d0:f0d5:b88d:1d1a:555e:2f6b:3148] \
+                         -r http://[505:6847:c778:61a1:5c6d:e802:d291:8191] \
+                         -r http://hc3fycfadz7fkapp62fqi6llioe46fvis6wuswfobl5ghc2u7snq.b32.i2p \
+                         -r http://w6vtcpbir5vvokwdqqbqlrdtnzwyfc4iyqn6owxuyjeppszuydutqwqd.onion
+```
+* optionally, delegate to `crontab -e`