Merge browsertest-website and browsertest-website-version builders

Minor updates to jobs:

browsertests-MultimediaViewer-en.wikipedia.beta.wmflabs.org-windows_7-internet_explorer-8-sauce
browsertests-MultimediaViewer-en.wikipedia.beta.wmflabs.org-windows_7-internet_explorer-9-sauce
browsertests-MultimediaViewer-en.wikipedia.beta.wmflabs.org-windows_8.1-internet_explorer-11-sauce
browsertests-VisualEditor-en.wikipedia.beta.wmflabs.org-windows_8.1-internet_explorer-11-sauce

Paired-With: Tobi Gritschacher
Bug: T669
Change-Id: I09c7819eb19fe64b865163ac85a601f9c8683a8c