Improve qc context definition and reporting

[gwbres]

Introduce a QcContext structure to manage Input Data (both parsed data as Rinex and file sources as PathBuf).

The current implementation makes it hard to report which file was provided by user, which is a nice teqc feature we should emulate.

The new QcContext defines the provided Data (files pool): and the idea is to build them once at the start of the application and avoid copying this structure.

The QC report creation methods have also been improved. The previous API involved two calls: QcReport::new and then QcReport::to_html(). The problem with this dual process is the need to store the context in between, which we want to avoid for efficiency.

This is now simplified to QcReport::html() to create the report, at once.

The workspace has been moved to rinex-cli/workspace and is managed better thanks to the use of std::Path instead of simple strings. It is not possible to customize the workspace location at the moment, that will come later.

Improved the QC reporting:

• report source files and their types
• move Header section into an HtmlReport implementation, inside header.rs.
• have more structures implement HtmlReport to report them easily
• Separate analysis better, in the generated report