1.18.2: Update environment and fix spelling error in German

Bug fixes:

• lib-french-revolutionary-calendar: 1.8.0 -> 1.8.2
  https://github.com/caarmen/french-revolutionary-calendar/blob/master/CHANGELOG.md

  1.8.2 (2018-07-04)

  • Update to Kotlin 1.2.51
  • Issue #21: Fix misspelling of german word Wiesenmonat for Prairial.
    1.8.1 (2018-04-01)
  • Fixed VonMadler calculation errors in time zones other than Paris.
  • Fixed Romme calculations after 23:00 in some time zones.

Update environment:

• kotlin: 1.1.51 -> 1.2.51
• support lib: 25.3.1 -> 27.1.1
• android gradle plugin: 2.3.3 -> 3.1.3
• compileSdkVersion: 26 -> 27
• targetSdkVersion: 26 -> 27
• ben-manes: 0.15.0 -> 0.20.0

Remove some unnecessary gradle configuration to "filter resources".