add: complete documentation

fix: unused options in redis
fix: compatibility between python 2-3
fix: forgot vars declarations
fix: carry conditions in listing redis keys
fix: listing redis list keys
fix: removed duplicated tasks when they are listed
fix: index number when redis DB are listed
fix:  some error levels in log
fix: renamed *proc* -> *tasks* files
fix: added the process manager backend for 'tasks' options, thinking in future  to add new process managers

doc/source/installation.rst

@@ -0,0 +1,45 @@
+Installation
+============
+
+Using PIP
+---------
+
+The easiest way to install enteleteaor is from Pypi. To do this, only run:
+
+.. code-block:: bash
+
+    # pip install enteletaor
+
+Then run enteleteaor writing:
+
+.. code-block:: bash
+
+    # enteleteaor -h
+
+From source
+-----------
+
+Also, you can download source code from github using git:
+
+.. code-block:: bash
+
+    git clone https://github.com/cr0hn/enteleteaor.git enteleteaor
+
+Next you need to install dependencies from ``requirements.txt``:
+
+.. code-block:: bash
+
+    pip install -r requirements.txt
+
+
+.. note::
+
+   If you're not running enteleteaor in a virtualenv, probably you need tu be root to install requirements. So, you can use ``sudo`` command.
+
+Finally you can run enteleteaor:
+
+.. code-block:: bash
+
+    # cd enteleteaor_lib
+    # python enteleteaor.py -h
+