add README file

README

@@ -0,0 +1,102 @@
+                          Virtual Haskell Environment
+
+What is it?
+-----------
+virthualenv is a tool (inspired by Python's virtualenv)
+to create isolated Haskell environments.
+
+
+What does it do?
+----------------
+It creates a sandboxed environment in a .virthualenv/ sub-directory
+of your project, which, when activated, allows you to use regular Haskell tools
+(ghc, ghci, ghc-pkg, cabal) to manage your Haskell code and environment.
+It's possible to create an environment, that uses different GHC version
+than your currently installed. Very simple emacs integration mode is included.
+
+Basic usage
+-----------
+First, choose a directory where you want to keep your
+sandboxed Haskell environment, usually a good choice is a directory containing
+your cabalized project (if you want to work on a few projects
+(perhaps an app and its dependent library), just choose any of them,
+it doesn't really matter). Enter that directory:
+
+> cd ~/projects/foo
+
+Next, create your new isolated Haskell environment
+(this is a one time only (per environment) step):
+
+> virthualenv
+
+Now, every time you want to use this enviroment, you have to activate it:
+
+> source .virthualenv/bin/activate
+
+That's it! Now it's possible to use all regular Haskell tools like usual,
+but it won't affect your global/system's Haskell environment, and also
+your per-user environment (from ~/.cabal and ~/.ghc) will stay the same.
+All cabal-installed packages will be private to this environment,
+and also the external environments (global and user) will not affect it
+(this environment will only inherit very basic packages,
+mostly ghc and Cabal and their deps).
+
+When you're done working with this environment, enter command 'deactivate',
+or just close the current shell (with exit).
+
+> deactivate
+
+Advanced usage
+--------------
+The only advanced usage is using different GHC version.
+This can be useful to test your code against different GHC version
+(even against nightly builds).
+
+First, download binary distribution of GHC for your platform
+(e.g. ghc-7.0.4-i386-unknown-linux.tar.bz2),
+then create a new environment using that GHC:
+
+> virthualenv --ghc=/path/to/ghc_something.tar.bz2
+
+Then, proceed (with [de]activation) as in the basic usage case.
+
+Misc
+----
+virthualenv has been tested on i386 Linux and FreeBSD systems,
+but it should work on any Posix platform. External (from tarball) GHC feature
+requires binary GHC distribution compiled for your platform,
+that can be extracted with tar and installed with
+"./configure --prefix=PATH; make install".
+
+FAQ
+---
+Q: Can I use it together with tools like cabal-dev or capri?  
+A: No. All these tools work more or less the same (wrapping cabal command,
+   setting GHC_PACKAGE_PATH env variable), so something will probably break.
+
+Q: Using GHC from tarball fails, when using FreeBSD with a bunch of make tool  
+   gibberish. What do I do?  
+A: Try '--make-cmd=gmake' switch.
+
+Q: Can I use virthualenv inside virthualenv?  
+A: No. It may be supported in future versions.
+
+Q: Does it work on x64 systems?  
+A: It hasn't been tested, but there's no reason why it shouldn't.
+
+Q: Will it work on Mac?  
+A: I doubt it. It should be easy to make it work there with system's GHC,
+   Using GHC from tarball will be probably harder. I don't have any mac
+   machines, so you're on your own, but patches/ideas/questions are welcome.
+
+Q: Will it work on Windows?  
+A: I really doubt it would even compile. I don't have access to any windows
+   machines, so you're on your own, but patches/ideas/questions are welcome.
+   Maybe it would work on cygwin.
+
+Q: Does it require bash?  
+A: No, it should work with any POSIX-compliant shell. It's been tested with
+   bash, bash --posix, dash, zsh and ksh.
+
+Q: Can I use it with a different haskell package repository than hackage?  
+A: Yes, just adjust the url in .virthualenv/cabal/config file.

virthualenv.cabal

@@ -84,7 +84,7 @@ Package-url:         http://hackage.haskell.org/package/virthualenv
 
 Tested-with:         GHC == 6.12.3, GHC == 7.0.4
 
-Data-files:          virthualenv.el
+Data-files:          virthualenv.el, README
 
 Extra-source-files:  skeletons/activate, skeletons/cabal, skeletons/cabal_config