Simple intro for dimred notebook
Fix ordered list in INSTALL.md
added a few convienience methods and debug output
obtain from generic method
minor updates
added Gaussian mixture model notebook
Merge pull request #1737 from karlnapf/develop

GMM notebook
minor updates
Merge pull request #1738 from karlnapf/develop

minor updates to GMM notebook
Merge pull request #1736 from iglesias/feature/notebook/dimred

Simple intro for dimred notebook
Updated tapkee notebook
Simple notebook to demonstrate how to learn from streamed sparse features.