doc: added installation info

Author: janithcooray

README.markdown

@@ -680,7 +680,29 @@ each request.
 
 [Back to TOC](#table-of-contents)
 
-Installation
+Installation - Build from source
+============
+
+```sh
+# Clone latest release , assuming v0.29
+wget https://github.com/openresty/lua-resty-redis/archive/refs/tags/v0.29.tar.gz
+
+# Extract
+tar -xvzf v0.29.tar.gz
+
+# go into directory
+cd lua-resty-redis-0.29
+
+export LUA_LIB_DIR=/usr/local/openresty/site/lualib
+
+# Compile and Install
+make install
+
+# Now compiled path will be outputted
+# /usr/local/lib/lua/resty = lua_package_path in nginx conf
+```
+
+Installation Notes
 ============
 
 If you are using the OpenResty bundle (http://openresty.org ), then