Added algorithms summary (FN)
Delete kmeans_c_extension.so
added build script for C extension. added init file for demos.
removed mini_batch and soft k-means methods for first release.
added parameter 'return_centers' to calculate_centers in order to only return the calculated cluster centers if it is necessary (i.e. for demo/testing purposes).
added saving of assignment data in the iteration step of the python implementation.
added shell script to execute performance demo.
modified the C extension such that it also returns the assignment data.
Make some comments for the py files and c files

Conflicts:
	kmeans/extension/kmeans_c_extension.cpp
	kmeans/extension/kmeans_chunk_center.cpp
added KmeansBinaryFileDataImporter which imports data using numpy.load. the importer.get_data() methods now return a numpy array instead of a list of numpy arrays. modified KmeansFileDataImporter as well as the C extension accordingly. added a wrapper for KmeansRandomDataGenerator to save data in a binary file.
Merge pull request #1 from florianlitzinger/kmeans_r1

kmeans r1
merged from master.