Merge branch 'release/0.1'

* release/0.1: (21 commits)
  Update versionCode to 5
  Create new screenshots on Nexus5 & Nexus9
  Omit a few this. statements
  Add german translation for sharing article
  Add share intent for action_share in ArticleActivity
  Refactor: Put menu methods further up in ArticleActivity
  Never show share text on action_share
  Add action_share to menu_article
  Import share icons
  Use article margins in article activity layout
  Create article margins for all screen sizes
  Rename activity_margins in dimens.xml
  Remove all obsolete layout files
  Improve action_browser with ifRoom|withText and icon
  Import correct open_browser icon
  Use light theme and white textColorPrimary
  Upgrade appcompat-v7 from 21.0.2 to 21.0.3
  Remove unused ApplicationTest.java
  Add crashlytics to build.gradle and to MainActivity
  Ignore crashlytics-build.properties
  ...