Copy README.txt contents to README.md

so the github page is restored.

README.md

-Just to trigger automatic builds of docker image.
+Prerequisites to build from source:
+	Java SDK (preferably Oracle/Sun or OpenJDK) 1.7.0 or higher
+          Non-linux operating systems and JVMs: See https://trac.i2p2.de/wiki/java
+          Certain subsystems for embedded (core, router, mstreaming, streaming, i2ptunnel) require only Java 1.6
+	Apache Ant 1.7.0 or higher
+	The xgettext, msgfmt, and msgmerge tools installed
+	  from the GNU gettext package http://www.gnu.org/software/gettext/
+	Build environment must use a UTF-8 locale.
 
-Sorry for the mess in the root directory.
+To build:
+	On x86 systems do:
+		ant pkg
 
-TODO: Change content :)
+	On non-x86, use one of the following instead:
+		ant installer-linux
+		ant installer-freebsd
+		ant installer-osx
 
-(hub.docker.io requires a Dockerfile + README.md in root, to build from a repo)
+	Run 'ant' with no arguments to see other build options.
+	See INSTALL.txt or https://geti2p.net/download for installation instructions.
+
+Documentation:
+	https://geti2p.net/how
+	API: http://docs.i2p-projekt.de/javadoc/
+	     or run 'ant javadoc' then start at build/javadoc/index.html
+
+Latest release:
+	https://geti2p.net/download
+
+To get development branch from source control:
+	https://geti2p.net/newdevelopers
+
+FAQ:
+	https://geti2p.net/faq
+
+Need help?
+	IRC irc.freenode.net #i2p
+	http://forum.i2p/
+
+Bug reports:
+	https://trac.i2p2.de/report/1
+
+Contact information, security issues, press inquiries:
+	https://geti2p.net/en/contact
+
+Twitter:
+	@i2p, @geti2p
+
+Licenses:
+	See LICENSE.txt