Documentation: brief introduction and installation steps

docs/index.rst

@@ -1,4 +1,30 @@
 out-of-tree
 ===========
 
-out-of-tree kernel {module, exploit} development tool
+*out-of-tree* is the kernel {module, exploit} development tool.
+
+*out-of-tree* was created on the purpose of decreasing complexity of
+environment for developing, testing and debugging Linux kernel
+exploits and out-of-tree kernel modules (that's why tool got a name
+"out-of-tree").
+
+While I'm trying to keep that documentation up-to-date, there may be
+some missing information. Use ``out-of-tree --help-long`` for checking
+all features.
+
+If you found anything missed here, please make a pull request or send
+patches to patch@dumpstack.io.
+
+If you need personal support, your company is interested in the
+project or you just want to share some thoughts -- feel free to write
+to root@dumpstack.io.
+
+Contents
+========
+
+:ref:`Keyword Index <genindex>`
+
+.. toctree::
+
+   introduction.rst
+   installation.rst