Add licence and readme.

LICENCE

+Copyright 2017 Dominik George <d.george@tarent.de>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to
+deal in the Software without restriction, including without limitation the
+rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.

README.md

+Universal strace wrapper for debugging
+======================================
+
+stracify is a universal strace wrapper for debugging purposes. It replaces
+an arbitrary binary with itself, ensuring it will be called as close to the
+original as possible, and also includes some management code to wrap or
+unwrap binaries.
+
+Installation
+============
+
+Install mksh as a dependency, then install the stracify script into the
+PATH.
+
+Wrapping a binary
+=================
+
+Wrapping a binary is done using the command `sudo stracify /usr/bin/foo`.
+
+An optional strace filter expression can be passed, like `sudo stracify
+/usr/bin/foo open,write`.
+
+On Debian systems, care is taken to register the diversion with dpkg.
+
+Finding the strace output of calls
+==================================
+
+The output fiels are stored in a directory structure organised like this:
+
+```
+/var/log/stracify/
+ |- usr_bin_foo/
+     |- root/
+         |- strace_2017-09-08T14:19:57+02:00_11911.log.11924
+     |- user1/
+         |- ...
+```
+
+This structure was chosen so all users can run the wrapped binary, but
+without opening up the strace outputs from one user's calls to others. The
+template for the log file names is `strace_$date_$pif.$childpid`.
+
+Please note that due to the architecture of stracify, the logs will contain
+quite a bit of trace from stracify and mksh themselves. This is not very
+pretty, but better than losing functionality in the wrapped binary due to a
+crooked call.
+
+Unwrapping a binary
+===================
+
+A binary can be unwrapped using the command `stracify unwrap /usr/bin/foo`.