Update Icecat to 45.6.0

Merged username-removed-85639 requested to merge Manizuca/fdroiddata:IceCat into master

Still not released by GNU, but firefox ESR 45.6.0 is 3 weeks old. As i'll be 2 month without connection, i think that is better to just release it here now.

PS: @krt i already updated the locales & script for fennec 51 and works with latest beta, it should work with final