Merge pull request #5 from vaporup/patch-2

Add doc for cross-packaging

README.md

@@ -58,6 +58,20 @@ Distro detection is performed by reading the `/usr/lib/os-release` and `/etc/os-
 
 ---
 
+## Cross-packaging for other Distributions
+
+You can create packages for different distributions  
+setting the environment variables `LURE_DISTRO` and `LURE_PKG_FORMAT`.
+
+```
+LURE_DISTRO=arch     LURE_PKG_FORMAT=archlinux lure build
+LURE_DISTRO=alpine   LURE_PKG_FORMAT=apk       lure build
+LURE_DISTRO=opensuse LURE_PKG_FORMAT=rpm       lure build
+LURE_DISTRO=debian   LURE_PKG_FORMAT=deb       lure build
+```
+
+---
+
 ## Repositories
 
 Unlike the AUR, LURE supports using multiple repos. Also unlike the AUR, LURE's repos are a single git repo containing all the build scripts. Inside each LURE repo, there should be a separate directory for each package containing a `lure.sh` script, which is a PKGBUILD-like build script for LURE. The default repository is hosted on Github: https://github.com/Arsen6331/lure-repo.