* refactor: const correctness
* refactor: fix some implicit conversions
* refactor: make local pointers const if their objects are not modified
* refactor: do not cast away const in torrent-cell-renderer
* refactor: remove call to deprecated gtk_icon_size_lookup_for_settings
* refactor: member functions that do not mutate their objects should be declared const
* chore: do not end comments with a semicolon
This way all the qualifiers (`const`, `volatile`, `mutable`) are grouped
together, e.g. `T const* const x` vs. `const T* const x`. Also helps reading
types right-to-left, e.g. "constant pointer to constant T" vs. "constant
pointer to T which is constant".
There're places where manual intervention is still required as uncrustify
is not ideal (unfortunately), but at least one may rely on it to do the
right thing most of the time (e.g. when sending in a patch).
The style itself is quite different from what we had before but making it
uniform across all the codebase is the key. I also hope that it'll make the
code more readable (YMMV) and less sensitive to further changes.
