[doc] install notes

README.md

 =====
 
 Minimalistic web interface to different search engines.
+
+
+### Installation
+
+*   install dependencies: `pip install -r requirements.txt`
+*   clone source: `git clone git@github.com:asciimoo/searx.git && cd searx`
+*   create a config file: `cp searx.conf_sample search.conf`
+*   edit your config (set your `secret_key`!)
+*   run `python potion/webapp.py` to start the application