finally got installation working

debian/control

@@ -5,6 +5,7 @@ Maintainer: Lubuntu Developers <lubuntu-devel@lists.ubuntu.com>
 Uploaders: Walter Lapchynski <wxl@ubuntu.com>
 Build-Depends: cmake (>= 2.8.11),
                debhelper (>= 11),
+               dh-exec,
                git,
                gpg-agent,
                libgpg-error-dev,

debian/rules

@@ -2,4 +2,4 @@
 export DH_VERBOSE = 1
 
 %:
-	dh $@
+	dh $@ --buildsystem=cmake

debian/trojita-plugin-qtkeychain.install

@@ -1 +1,2 @@
-usr/lib/*/trojita/trojita_plugin_QtKeychainPasswordPlugin.so*
+#!/usr/bin/dh-exec
+usr/lib/trojita/trojita_plugin_QtKeychainPasswordPlugin.so* /usr/lib/trojita/${DEB_HOST_MULTIARCH}

debian/trojita.install

@@ -1,4 +1,5 @@
+#!/usr/bin/dh-exec
 usr/bin/be.contacts
 usr/bin/trojita
-usr/lib/*/libtrojita_plugins.so*
+usr/lib/libtrojita_plugins.so* /usr/lib/trojita/${DEB_HOST_MULTIARCH}
 usr/share/applications/trojita.desktop