SaveFile check output formats

[Pavel Lobashov]

SaveFile support a lot of output formats
https://api.onlyoffice.com/docbuilder/integrationapi/cdocbuilder/savefile

Need to add test which cheack every combination of input format (builder.CreateFile) and output format.
Also check incorrect combinations (like save docx to csv)

[Dmitriy Rotatyy]

Fix: #152