REN-132 improved formatting and added some debug output (please remove after finishing)
REN-132 begin major refactoring (does not compile yet)
REN-123 Debian package build step
REN-132 Further refactoring (does not build yet)
REN-123 Fixed syntax error in debian dependency string
REN-132 Further refactoring
REN-132 Implemented new parser base
Merge branch 'develop' of https://github.com/3dcl/libcitygml into feature/REN-123-implement-cpack
REN-132 Bugfixes and Polygon sharing
REN 132 Fixed bugs, implemented coordinate transformation, refactoring

- Removed vrml application (no longer works and is not needed)
- Polygons no longer calculate normal arrays
- Removed libxml2 parser
REN-132 Fixed bugs implemented some features

- disable optimization (duplicate vertex removal) by default
- fixes transformation bugs (e.g. shared geometry must not be transformed)
- support address elements
- allow shared geometry to be referenced in the xml document before it
  is defined
REN-132 removed unused include breaking the build
REN-132 Added more nodetypes
REN-132 Add missing node type, skip unknown or unexpected elements
REN-132 Fixed tesselation
Catch file open errors
Compile fix
REN-132 Added FRN namespace elements, fixed duplicate vertex removal bug
Update .travis.yml

Changed order of apt-get calls
Update .travis.yml

hopfully that make the travis build work