LMDE7: adjust more packages

libcec6 becomes +  - libcec7

Add libqt5webengine5, libqt5webenginecore5 and libqt5webenginewidgets5

Refs: #97

Author: Bill Meek

roles/mythtv/vars/linux_mint_debian_edition/7.yml

@@ -74,7 +74,7 @@ packages:
   - libtool-bin
   - sqlite3
   - libcec-dev
-  - libcec6
+  - libcec7
   - libavc1394-dev
   - libiec61883-dev
   - libpulse-dev
@@ -108,6 +108,9 @@ qt5_packages:
   - qtscript5-dev
   - qt5-qmake
   - libqt5sql5-mysql
+  - libqt5webengine5
+  - libqt5webenginecore5
+  - libqt5webenginewidgets5
 
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