Some more documentation and cleanup of the procpool contrib.

contrib/procpools/README.txt

@@ -0,0 +1,40 @@
+
+ProcPools
+---------
+
+This contrib defines a process pool subsystem for Evennia.
+
+A process pool handles a range of separately running processes that
+can accept information from the main Evennia process. The pool dynamically
+grows and shrinks depending on the need (and will queue requests if there
+are no free slots available).
+
+The main use of this is to launch long-running, possibly blocking code
+in a way that will not freeze up the rest of the server. So you could 
+execute time.sleep(10) on the process pool without anyone else on the 
+server noticing anything. 
+
+This folder has the following contents: 
+
+ampoule/ - this is a separate library managing the process pool. You 
+           should not need to touch this.
+
+Python Procpool
+---------------
+python_procpool.py - this implements a way to execute arbitrary python
+           code on the procpool. Import run_async() from this
+           module in order to use this functionality in-code
+           (this is a replacement to the in-process run_async
+           found in src.utils.utils).
+python_procpool_plugin.py - this is a plugin module for the python
+           procpool, to start and add it to the server. Adding it 
+           is a single line in your settings file - see the header
+           of the file for more info. 
+
+
+
+Adding other Procpools
+----------------------
+To add other types of procpools (such as for executing other remote languages
+           than Python), you can pretty much mimic the layout of python_procpool.py
+           and python_procpool_plugin.py.