adjusted eXist-db dependency to required 5.3.0

src/expath-pkg.xml

@@ -4,7 +4,7 @@
   name="http://e-editiones.org/tuttle"
   abbrev="tuttle" version="1.0.2" spec="1.0">
   <title>Tuttle - Git for eXist-db</title>
-  <dependency processor="http://exist-db.org" semver-min="5.0.0"/>
+  <dependency processor="http://exist-db.org" semver-min="5.3.0"/>
   <dependency package="http://e-editiones.org/roaster" semver-min="1.0.0"/>
   <dependency package="http://exist-db.org/apps/shared" semver-min="0.9.1"/>
 <!--  <dependency package="http://expath.org/ns/crypto" semver-min="5.0.0"/>-->