This adapts the updater to the new configuration locations (#18) and
changes the control flow so that first the script will detect if any
updates are necessary at all and then validate the configuration files
(respecting what parts will be updated), preparing for the actual update
tasks (as this is currently work-in-progress, those update tasks are
disabled for now.

Refers to #28

The updater should also check if an existing configuration that won't be
updated validates correctly with newer service binaries and stop the
process of updating if the check fails.

Refers to #28

Refers to #28

Refers to #18

Implements the core functionality of #28

This is required to correctly propagate exceptions from function calls.
Otherwise every call has to specify the "-EA" flag explicitly.

Refers to #28

Refers to #22

Refers to #28, #13

Refers to #28, #18, #13

Refers to #17

Refers to #18

Refers to #18

Refers to #18

Refers to #18

Refers to #18

Refers to #18, #29

Refers to #18, #28, #29

There is no need to test a status file for correctness as the status
class will simply create a new object with default values in case
parsing an existing file fails.

Refers to #22, #28

Refers to #18, #29

Refers to #29, #18, #28

Refers to #28

Refers to #28

Refers to #29

Refers to #28

Refers to #28

Refers to #28

Those objects are not meant to be instantiated directly but only using
the Deserialize() methods which takes care of creating a new object in
case deserializing fails for the status class.

This way the value is directly visible in the code where the property is
created, improving readability. Setting defaults in the constructor is
therefore not necessary any more.

Refers to #29