add a script to update deltachat-core

tools/update-core.sh

@@ -0,0 +1,42 @@
+
+# this script updates the deltachat-core sub-repository from github.
+#
+# - make sure, the deltachat-android directory is clean
+# - make sure, deltachat-core is committed successfull before calling this script
+# - the script assumes, deltachat-core is placed in the same directory as deltachat-android
+#
+# to simplify core-development, files in the submodule folder are replaced by 
+# symbolic links to ../deltachat-core afterwards
+
+# get to main directory
+cd ..
+
+# remove links to the files
+rm -r jni/messenger-backend/*
+rm -r jni/messenger-backend/.??*
+
+# check out submodules as present in the repository
+git submodule update --init --recursive
+
+# update submodule
+cd jni/messenger-backend
+git checkout master
+git pull
+
+# commit changes
+cd ../..
+git commit -am "Update messenger-backend submodule."
+
+# remove files downloaded just  for committing
+rm -r jni/messenger-backend/*
+rm -r jni/messenger-backend/.??*
+
+# re-link all files (symbolic links may contain arbitrary text, so no relative paths, please)
+cd ..
+ln --symbolic `pwd`/deltachat-core/src     deltachat-android-ii/jni/messenger-backend/src
+ln --symbolic `pwd`/deltachat-core/libs    deltachat-android-ii/jni/messenger-backend/libs
+ln --symbolic `pwd`/deltachat-core/cmdline deltachat-android-ii/jni/messenger-backend/cmdline
+cd deltachat-android-ii
+
+# back to tools directory
+cd tools