add README.source

debian/README.source

+This package uses quilt to manage all modifications to the upstream
+source.  Changes are stored in the source package as diffs in
+debian/patches and applied during the build.
+
+To configure quilt to use debian/patches instead of patches, you want
+either to export QUILT_PATCHES=debian/patches in your environment
+or use this snippet in your ~/.quiltrc:
+
+    for where in ./ ../ ../../ ../../../ ../../../../ ../../../../../; do
+        if [ -e ${where}debian/rules -a -d ${where}debian/patches ]; then
+                export QUILT_PATCHES=debian/patches
+        fi
+    done
+
+To get the fully patched source after unpacking the source package, cd to
+the root level of the source package and run:
+
+    quilt push -a
+
+The last patch listed in debian/patches/series will become the current
+patch.
+
+To add a new set of changes, first run quilt push -a, and then run:
+
+    quilt new <patch>
+
+where <patch> is a descriptive name for the patch, used as the filename in
+debian/patches.  Then, for every file that will be modified by this patch,
+run:
+
+    quilt add <file>
+
+before editing those files.  You must tell quilt with quilt add what files
+will be part of the patch before making changes or quilt will not work
+properly.  After editing the files, run:
+
+    quilt refresh
+
+to save the results as a patch.
+
+Alternately, if you already have an external patch and you just want to
+add it to the build system, run quilt push -a and then:
+
+    quilt import -P <patch> /path/to/patch
+    quilt push -a
+
+(add -p 0 to quilt import if needed). <patch> as above is the filename to
+use in debian/patches.  The last quilt push -a will apply the patch to
+make sure it works properly.
+
+To remove an existing patch from the list of patches that will be applied,
+run:
+
+    quilt delete <patch>
+
+You may need to run quilt pop -a to unapply patches first before running
+this command.