Placed in namespace ATxCommon.Monitoring, using its own timer to update
the values.

Important if it has already been removed before, otherwise the updater
would stop at this point.

This way an email will be sent to an admin if configured so they have a
chance to check what's going on.

Refers to #3

This usually happens when VS is building multiple projects at the same
time, hence running the prepare-script multiple times at once.

Megabytes have shown to be a bit clumsy in the configuration files, so
simply switch to the more useful Gigabytes unit.

Fixes #39

Refers to #36

Refers to #25

Refers to #24

Allow setting the log level explicitly from "Warn", "Info", "Debug" or
"Trace" in the configuration.

Default is "Info", fallback for invalid settings is "Debug".

Fixes #34

Fixes #32

- config validation
- reporting
- log file upload
- update-source folder structure
- permissions

Fixes #33