0.1: Changed pixelDetector to use topic list
began on skeleton for purple_classifier package
fixed CMakeLists and package.xml to be able to compile
finished first skeleton for purple classifier
Changed way of looping through image
0.3: Added rosutil library to pixelDetector, using getParam
Merge branch 'parameter_reformat' into develop
Object library package for handling object image pre-processing
Basic thresholding on single test image passed as argument
Renamed visiontest, added simple thresholding test with slider
Basic contour-based extraction of object from single image
First version of the image extraction.

Assumes a certain directory structure. The directory passed as input
should contain directories which contain images of the objects.

Extracted images will be output with the same directory structure to the
second input parameter.
Added support for single directory processing

Added some utility functions to reduce code reuse.
Making full use of custom struct instead of populating map
Moved directory processing to utility library
Updated references to utility library
Update includes, prototype for model construction
Merge updated blobdetection references from develop
Outputting models into YAML files, checking args

Extractor and model learner now check that they are receiving
the required arguments.
ModelLearner outputs YAML file of model parameters