update readme since we are no longer mapping everything in dev (#118)

README.md

@@ -14,10 +14,7 @@ We're setting out to change that: `try cmd` and commit---or not.
 `try` lets you run a command and inspect its effects before changing your live system. `try` uses Linux's [namespaces (via `unshare`)](https://docs.kernel.org/userspace-api/unshare.html) and the [overlayfs](https://docs.kernel.org/filesystems/overlayfs.html) union filesystem.
 
 Please note that `try` is a prototype and not a full sandbox, and should not be used to execute
-commands that you don't already trust on your system, (i.e. devices in `/dev` are
-mounted in the sandbox, and network calls are all allowed.) Please do not
-attempt any commands that will remove everything in /dev or write zeros to your
-disks.
+commands that you don't already trust on your system, (i.e. network calls are all allowed)
 
 <img src="docs/try_pip_install_example.gif" alt="try gif">
 
@@ -160,7 +157,7 @@ Any command that interacts with other users/groups will fail since only the
 current user's UID/GID are mapped. However, the [future
 branch](https://github.com/binpash/try/tree/future) has support for uid/mapping;
 please refer to the that branch's readme for installation instructions for the
-uid/gidmapper.
+uid/gidmapper (root access is required for installation).
 
 Please also report any issue you run into while using the future branch!