Refactor of examples/game_of_life

[jesper-olsen]

Description

Refactor of examples/game_of_life as follows:

1. Moved conway grid logic from main.rs to cell.rs - to better separate model & yew code.
2. Renamed cell.rs to conway.rs
3. Simplified and removed some codeblocks - e.g. directly count neighbours, instead of retuning them so that they can be counted...

Functionality is unchanged, LOC is reduced from 282 to 210 (~25%).

Fixes #0000

Checklist

• I have reviewed my own code
• I have added tests

[github-actions]

Size Comparison

examples	master (KB)	pull request (KB)	diff (KB)	diff (%)
async_clock	102.006	102.006	0	0.000%
boids	175.728	175.728	0	0.000%
communication_child_to_parent	94.526	94.526	0	0.000%
communication_grandchild_with_grandparent	107.470	107.470	0	0.000%
communication_grandparent_to_grandchild	102.744	102.744	0	0.000%
communication_parent_to_child	90.881	90.881	0	0.000%
contexts	107.571	107.571	0	0.000%
counter	87.850	87.850	0	0.000%
counter_functional	88.238	88.238	0	0.000%
dyn_create_destroy_apps	90.744	90.744	0	0.000%
file_upload	101.674	101.674	0	0.000%
function_memory_game	174.516	174.516	0	0.000%
function_router	351.228	351.228	0	0.000%
function_todomvc	163.154	163.154	0	0.000%
futures	231.769	231.769	0	0.000%
game_of_life	112.119	111.677	-0.442	-0.395%
immutable	189.780	189.780	0	0.000%
inner_html	81.536	81.536	0	0.000%
js_callback	111.297	111.297	0	0.000%
keyed_list	201.004	201.004	0	0.000%
mount_point	84.424	84.424	0	0.000%
nested_list	115.850	115.850	0	0.000%
node_refs	92.000	92.000	0	0.000%
password_strength	1753.896	1753.896	0	0.000%
portals	95.202	95.202	0	0.000%
router	320.293	320.293	0	0.000%
simple_ssr	142.319	142.319	0	0.000%
ssr_router	389.602	389.602	0	0.000%
suspense	117.522	117.522	0	0.000%
timer	90.345	90.345	0	0.000%
timer_functional	99.719	99.719	0	0.000%
todomvc	143.458	143.458	0	0.000%
two_apps	87.535	87.535	0	0.000%
web_worker_fib	136.750	136.750	0	0.000%
web_worker_prime	187.137	187.137	0	0.000%
webgl	84.146	84.146	0	0.000%

✅ None of the examples has changed their size significantly.