- Add new shared subcrate satrs-shared to split off some shared
components not expected to change very often.
- Renmame `satrs-core` to `satrs`. It is expected that sat-rs will remain
the primary crate, so the core information is superfluous, and core also
implies stability, which will not be the case for some time.
- Increased example modularization by moving the majority
of app logic inside dedicated modules
- Added a new `dyn_tmtc` feature for the satrs-example which is used
to configure the heap as the backing store for TMTC packages instead
of static stores.
- Added dedicated satrs-example chapter in satrs-book
