Merge pull request #3829 from nextcloud/370-alpha1

bump master to 3.7.0-alpha1

build.gradle

@@ -65,7 +65,7 @@ repositories {
 
 // semantic versioning for version code
 def versionMajor = 3
-def versionMinor = 5
+def versionMinor = 7
 def versionPatch = 0
 def versionBuild = 0 // 0-50=Alpha / 51-98=RC / 90-99=stable