README: update for conversion to markdown.

README

@@ -1,17 +1,55 @@
-See http://code.google.com/p/xbps for information.
+## XBPS
+
+The X Binary Package System (in short XBPS) is a new binary package system **designed and implemented from scratch**. Its goal is to be fast, easy to use, bug-free, featureful and portable as much as possible.
+
+The XBPS code is totally compatible with POSIX/SUSv2/C99 standards, and released with a **Simplified BSD license (2 clause)**. There is a well documented API provided by the XBPS Library that is the basis for its frontends to handle binary packages and repositories. Some highlights:
+
+ * Supports multiple local and remote repositories (FTP/HTTP/HTTPS).
+ * SHA256 hashes for package metadata, files and binary packages.
+ * Supports package states (ala dpkg) to mitigate broken package installs/updates.
+ * Ability to resume partial package install/updates.
+ * Ability to unpack only files that have been modified in package updates.
+ * Ability to use virtual packages.
+ * Ability to replace packages.
+ * Ability to put packages on hold (to never update them. NEW in 0.16).
+ * Ability to preserve/update configuration files.
+ * Ability to force reinstallation of any installed package.
+ * Ability to downgrade any installed package.
+ * Ability to execute pre/post install/remove/update scriptlets.
+ * Ability to check package integrity: missing files, hashes, missing or unresolved (reverse)dependencies, dangling or modified symlinks, etc.
+ * Low memory footprint.
+ * Fast dependency resolver and sorting algorithms.
+
+The latest stable version **0.24** was released on **May 2nd, 2013**.
+
+### Build requirements
 
 To build this you'll need:
 
-  - GNU make, pkg-config, zlib, openssl, libarchive[0] >= 3.0.2, confuse[1] >= 2.7.
+  - GNU make
+  - pkg-config
+  - zlib
+  - openssl
+  - libarchive[0] >= 3.0.2
+  - confuse[1] >= 2.7
 
 and optionally:
 
   - graphviz and doxygen (--with-api-docs) to build API documentation.
   - atf >= 0.15 (--with-tests) to build the Kyua test suite [2].
 
-Just run ./configure && make && make install. By default PREFIX is set
+### Build instructions
-to `/usr/local', can be changed by setting --prefix. The DESTDIR variable
+
-is also supported for package managers.
+Standard configure script (not generated by GNU autoconf).
+
+```
+./configure --prefix=/blah
+make -jX
+make install
+```
+
+By default PREFIX is set `/usr/local` and may be changed by setting `--prefix` in the
+`configure` script. The `DESTDIR` variable is also supported at the install stage.
 
 There are some more options that can be tweaked, see them with
 `./configure --help'.