Resolve "A quick and dirty GW workflow"

Closes #86 (closed). The workflow is activated by selecting a "Calculate a DFT bandstructure" within the GW page in Control Generator. Afetr that the input files contain the archive with two directories: 'DFt' and 'GW', and a readme file prompting the user to archive all the outputs in the single archive after calculating. In the Output analyzer the logic of working with archives was added. The user first chooses the output file to analyze; the band structure is collected and displayed on one graph.