Update README.md

Author: birdayz

README.md

@@ -1,5 +1,13 @@
-Kafka CLI
+#Kafka CLI
 
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+## Installing
+Install from source:
+
+```go get -u github.com/infinimesh/kaf```
+
+Install binary:
+
+```curl https://raw.githubusercontent.com/infinimesh/kaf/master/godownloader.sh | BINDIR=$HOME/bin bash```