add build document

BUILD.md

@@ -0,0 +1,36 @@
+# Building Databunker
+
+## Build for release
+
+```
+./release.sh
+```
+
+It will generate **databunker** executable. HTML files are built inside executable.
+
+## Debug version
+
+```
+./build.sh
+```
+
+It will generate **databunker** executable that can be run on the same box.
+Web UI will be fetched from ui directory.
+
+## Build container
+
+```
+docker build -t paranoidguy/databunker:latest .
+```
+
+It will generate "paranoidguy/databunker" container.
+
+Other usefull commands for working with docker:
+
+```
+docker rm dbunker
+docker kill dbunker
+docker container stats dbunker
+docker run --rm -ti alpine
+/bin/busybox wget localhost:3000
+```