Update the links in the README files following github migration.

Also add a README.md file for easier online reading on github.
diff --git a/README b/README
index c67823b..b687283 100644
--- a/README
+++ b/README
@@ -1,10 +1,11 @@
 open-vcdiff is an encoder and decoder for the VCDIFF format, as described in
 RFC 3284 : The VCDIFF Generic Differencing and Compression Data Format
 (http://www.ietf.org/rfc/rfc3284.txt)
+
 A library with a simple API is included, as well as a command-line executable
 that can apply the encoder and decoder to source, target, and delta files.
 For further details, please refer to:
-http://code.google.com/p/open-vcdiff/wiki/HowToUseOpenVcdiff
+https://github.com/google/open-vcdiff/wiki/How-to-use-openvcdiff
 
 See INSTALL for (generic) installation instructions for C++: basically
    ./configure && make && make install
@@ -39,5 +40,4 @@
    make check
 
 For further details, please refer to:
-http://code.google.com/p/open-vcdiff/wiki/HowToUseOpenVcdiff
-
+https://github.com/google/open-vcdiff/wiki/How-to-use-openvcdiff
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..6bc8449
--- /dev/null
+++ b/README.md
@@ -0,0 +1,45 @@
+# open-vcdiff README
+
+open-vcdiff is an encoder and decoder for the VCDIFF format, as described in [RFC 3284](http://www.ietf.org/rfc/rfc3284.txt): The VCDIFF Generic Differencing and Compression Data Format.
+
+A library with a simple API is included, as well as a command-line executable that can apply the encoder and decoder to source, target, and delta files. For further details, please refer to [this link](https://github.com/google/open-vcdiff/wiki/How-to-use-openvcdiff).
+
+See [INSTALL](https://github.com/google/open-vcdiff/blob/master/INSTALL) for (generic) installation instructions for C++: basically
+```bash
+./configure && make && make install
+```
+
+This should compile the unit tests as well as `vcdiff`, a simple command-line utility to run the encoder and decoder.  Typical usage of vcdiff is as follows (the `<` and `>` are file redirect operations, not optional arguments):
+```bash
+vcdiff encode -dictionary file.dict < target_file > delta_file
+vcdiff decode -dictionary file.dict < delta_file  > target_file
+```
+
+To see the command-line syntax of vcdiff, use `vcdiff --help` or just `vcdiff`.
+
+To call the encoder from C++ code, assuming that dictionary, target, and delta are all `std::string` objects:
+```c++
+#include <google/vcencoder.h>  // Read this file for interface details
+
+// [...]
+
+open_vcdiff::VCDiffEncoder encoder(dictionary.data(), dictionary.size());
+encoder.SetFormatFlags(open_vcdiff::VCD_FORMAT_INTERLEAVED);
+encoder.Encode(target.data(), target.size(), &delta);
+```
+
+Calling the decoder is just as simple:
+```c++
+#include <google/vcdecoder.h>  // Read this file for interface details
+
+// [...]
+
+open_vcdiff::VCDiffDecoder decoder;
+decoder.Decode(dictionary.data(), dictionary.size(), delta, &target);
+```
+
+When using the encoder, the C++ application must be linked with the library options `-lvcdcom` and `-lvcdenc`; when using the decoder, it must be linked with `-lvcdcom` and `-lvcddec`.
+
+To verify that the package works on your system, especially after making modifications to the source code, please run the unit tests using `make check`.
+
+For further details, please refer to [this link](https://github.com/google/open-vcdiff/wiki/How-to-use-openvcdiff).