Import readme and license.

README.md

@@ -0,0 +1,28 @@
+## XT Toolchain
+This is a LLVM/Clang/LLD based mingw-w64 toolchain. It currently supports C and C++, and provides
+a variety of tools including IDL, message and resource compilers. The XT Toolchain is also the
+official build environment for compiling XT software, including the FerretOS. Currently, it is
+targeted at Linux host only, however it should be possible to build it in MSYS2 as well.
+
+Benefits of a LLVM based MinGW toolchain are:
+ * Single toolchain targeting all architectures (i686, x86_64, armv7 and aarch64),
+ * Support for generating debug info in PDB format,
+ * Support for targeting ARM/AARCH64 architectures and ability to produce Windows ARM binaries.
+
+This software includes:
+ * CMake
+ * LLVM
+ * Make
+ * Mingw-w64
+ * Ninja
+ * Wine
+
+This software is based on ["LLVM MinGW Toolchain"](https://github.com/mstorsjo/llvm-mingw).
+
+## Licensing
+The XTchain project includes the scripts for building and assembling a toolchain as well as wrappers
+for LLVM tools and environmental shell. These are licensed under the GPLv3 license. It covers only
+mentioned components that are provided by XTchain directly. For more information on that, refer to
+the COPYING.md file. The final pre-built toolchain is covered by the licenses of the individual,
+external projects. The full list of software incorporated into this toolchain is available in the
+README.md file.