Prepare building environment for F-Droid
Removed Gradle submodule (is provided as wrapper in lib/)
Removed commented debug code
Undo signingConfigs removal (F-droid import ignores this field so this was an accidental removal)
Pinned syncthing submodule to v0.9 release
Removed wrapper task in build.gradle
Match original build.graddle
Set gradle properties for F-Droid
Removed echo output in build script
Always initialise submodules when building natives
Depend on buildNative task when compiling
Fixes non-existing directory and invalid path errors in copyNative
Removed local gradle wrapper, we assume gradlew is used to run the build script
Cross-compiled files are found in $GOBIN/linux_arm/
Removed build script as buildNative is executed during Gradle prebuild
Removed submodule golang-crosscompile
Added createWrapper task in build.gradle and updated README w.r.t. gradlew
Use cryptographically strong hash of the changeset data instead of branch for golang
Moved submodules to ext/ folder and updated README
Exit build script when it fails and cleanup when done