update README to be markdown compliant

BUG=chromium:878440
TEST=read it

Change-Id: I7b61f2a363393aa24f60f0e8a3a125af193c9c90
Reviewed-on: https://chromium-review.googlesource.com/1229245
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
diff --git a/README b/README.md
similarity index 71%
rename from README
rename to README.md
index 393041e..4d92f6f 100644
--- a/README
+++ b/README.md
@@ -1,3 +1,5 @@
+# Verity
+
 Verity is the userspace tool for creating integrity hashes for a device image.
 
 This tool is a frontend for dm-bht, a device-mapper friendly block hash
@@ -12,34 +14,42 @@
 
 This tool creates an image of the format:
 
-[hash of hash of blocks n ... n+n-1]
-[hash of hash of blocks 0 ... n-1]
-[...]
-[hash of block 1]
-[hash of block 0]
+* [hash of hash of blocks n ... n+n-1]
+* [hash of hash of blocks 0 ... n-1]
+* [...]
+* [hash of block 1]
+* [hash of block 0]
 
 Upon completion, the hash of the root hash will be printed to standard
 out.  The root hash, tree depth, number of hashed blocks, and cryptographic
 hash algorithm used must be supplied to the dm-verity when configuring a
 device.
 
+## Building
 
 To build outside of Chromium OS:
-- make all WITH_CHROME=0
+```sh
+make
+```
+
+## Example Usage
 
 To use:
+```sh
+./verity mode depth alg image hash_image [root_hexdigest]
+```
 
-./build-opt/verity mode depth alg image hash_image [root_hexdigest]
+For example:
+```sh
+dd if=/dev/zero of=/tmp/image bs=4k count=512
+./verity create 2 sha256 /tmp/image /tmp/hash | tee table
+# ...
+cat table
+ls -la /tmp/hash
+```
 
-E.g.,
-   dd if=/dev/zero of=/tmp/image bs=4k count=512
-  ./build-opt/verity create 2 sha256 /tmp/image /tmp/hash | tee table
-  # ...
-  cat table
-  ls -la /tmp/hash
+## Licensing
 
-
-Licensing note:
 All the source code is licensed GPLv2 to be completely kernel compatible.
 The Makefiles are from the parent project and are licensed under a BSD-style
 license.