fix several Lintian tags, create libubimockresolver0 package

Fixes:
```
W: ubiquity-frontend-gtk: package-name-doesnt-match-sonames libubimockresolver0
W: ubiquity-frontend-gtk: non-dev-pkg-with-shlib-symlink usr/lib/x86_64-linux-gnu/libubimockresolver.so.0.0.0 usr/lib/x86_64-linux-gnu/libubimockresolver.so
E: ubiquity-frontend-gtk: no-shlibs-control-file usr/lib/x86_64-linux-gnu/libubimockresolver.so.0.0.0
E: ubiquity-frontend-gtk: postinst-must-call-ldconfig usr/lib/x86_64-linux-gnu/libubimockresolver.so.0.0.0
E: ubiquity-frontend-gtk: postrm-should-call-ldconfig usr/lib/x86_64-linux-gnu/libubimockresolver.so.0.0.0
E: oem-config-gtk: python-script-but-no-python-dep usr/sbin/oem-config-remove-gtk
```

Overridden:
```
W: ubiquity-frontend-gtk: menu-command-not-in-package usr/share/menu/ubiquity-frontend-gtk:5 usr/bin/ubiquity
W: ubiquity-frontend-kde: desktop-command-not-in-package usr/share/applications/kde4/ubiquity-kdeui.desktop ubiquity
```

There are still many Lintian tags left in the Ubiquity package:
```
E: ubiquity: no-debconf-config
W: ubiquity: malformed-prompt-in-templates debian-installer/dummy
W: ubiquity: malformed-question-in-templates debian-installer/framebuffer
W: ubiquity: using-first-person-in-templates ubiquity/text/login_pass
W: ubiquity: using-first-person-in-templates ubiquity/text/login_encrypt
W: ubiquity: using-first-person-in-templates ubiquity/text/crash_text_label
W: ubiquity: malformed-prompt-in-templates ubiquity/install/filesystem-images
W: ubiquity: malformed-question-in-templates ubiquity/install/generate-blacklist
W: ubiquity: malformed-question-in-templates ubiquity/partman-failed-unmount
W: ubiquity: using-question-in-extended-description-in-templates ubiquity/partman-failed-unmount
W: ubiquity: using-first-person-in-templates ubiquity/text/no_wireless
W: ubiquity: using-question-in-extended-description-in-templates ubiquity/partitioner/heading_one
W: ubiquity: using-question-in-extended-description-in-templates ubiquity/partitioner/heading_dual
W: ubiquity: using-question-in-extended-description-in-templates ubiquity/partitioner/heading_multiple
W: ubiquity: using-question-in-extended-description-in-templates ubiquity/partitioner/heading_no_detected
W: ubiquity: malformed-prompt-in-templates debian-installer/dummy
E: ubiquity: unknown-template-type terminal
W: ubiquity: using-question-in-extended-description-in-templates disk-detect/activate_mdadm
W: ubiquity: using-question-in-extended-description-in-templates disk-detect/activate_dmraid
W: ubiquity: using-question-in-extended-description-in-templates partman/unmount_active
E: ubiquity: unknown-template-type entropy
E: ubiquity: postrm-does-not-call-updaterc.d-for-init.d-script etc/init.d/ubiquity
W: ubiquity: init.d-script-not-marked-as-conffile etc/init.d/ubiquity
E: ubiquity: init.d-script-not-included-in-package etc/init.d/ubiquity
```