Feature/maintainability

[maximilien-noal]

A lot of small changes fixing issues such as:

• warnings about exceptions not being used in catch statements.
• The usage of Path.GetFileName, Path.GetFileNameWithoutExtension, string.IsNullOrWhiteSpace, string.TrimEnd when appropriate
• Added more documentation
• Moved comments and splitted some longs ifs so they fit in a screen (no scrolling)
• Adding braces everywhere
• The introduction of interpolated strings instead of the " a " + " b" syntax (suggestion from Visual Studio) in a few places
• Subjective code style fixes (applied by the CodeMaid extension for VisualStudio)
• The source-code was moved inside a /src folder, which allows for a /tests folder later (which would contain unit tests)