Feature updates

• Dataset metafeatures are generated and stored during dataset upload.
• Supports random, meta and average recommender. Need to add knowledgebase for meta recommender to be useful.
• Added UI datasets details page. Shows preview of the data, metafeatures.
• UI improvements. Algo and parameter descriptions and documentation links, 'no capacity' errors if no machines available when attempting to start an algorithm, etc.
• Improved build process. node_modules generated during docker build instead of local build, smaller images, removed some unnecessary packages, etc.
• SemanticUI CSS added to project, so once it's been built internet access is no longer required to run.
• Python unit tests with code coverage.