Print errors when either sh, wget or unzip are not available.
Print error message if Eigen 3 is not found.
Add library path for MacOS.
Check if endian.h exists.
Merge pull request #82 from AlexanderFabisch/mac-issues

Mac issues
Move todo list to github issue tracking.
Update main page.
Add applications.
Move library comparison to new file.
Add link to getting started.
Document XOR example.
Merge pull request #90 from OpenANN/doc-cleanup

Doc cleanup
Improve documentation layout.
Extend howto.
Merge pull request #93 from OpenANN/doc-cleanup

Doc cleanup