[Maintenance] Standardise naming of binaries in examples

[kanerogers]

Background

At the moment, each of our examples is called.. lots of different things. Sometimes that's to get around conflicts with targets (eg. the lib is built as hotham_simple_scene so the binary can't be called hotham_simple_scene), other times it's just my laziness.

Solution

Simple naming convention:

• The lib target is just called by the project name (eg. hotham_simple_scene).
• The bin target is the project name, with a _desktop suffix (eg. hotham_simple_scene_desktop)

To change the name of a bin target, just modify the Cargo.toml manifest to add / change the following:

[[bin]]
name = "hotham_simple_scene_desktop"
path = "src/main.rs"