Added more content to the slides

Filled slides about
  - Build-Tools
  - API-Docs
Added examples to integreate in slides

Added several GeoExt2-examples for integration in the slides:
  - MapPanel
  - WMS Capabilities Grid
  - LayerTree
Use local examples in slides
Reworked the GeoExt-Future paragraph
Redesigned the imprint slide
Add coauthor and company slide.
Add myself to imprint.