Adding TOML config format as an option instead of JSON

[riffnshred]

Description
TOML is easier to read and less prone to user errors.

For exemple:

debug = false
live_mode = true
loglevel = "INFO"

[boards]
[boards.clock]
clock_rgb = ""
date_rgb = ""
duration = 15
flash_seconds = true
hide_indicator = false
preferred_team_colors = true

[boards.scoreticker]
preferred_teams_only = false
rotation_rate = 5

[boards.seriesticker]
preferred_teams_only = true
rotation_rate = 5

[boards.standings]
conference = "eastern"
divisions = "north"
preferred_standings_only = true
standing_type = "wild_card"

[preferences]
end_of_day = "8:00"
live_game_refresh_rate = 10
location = ""
sog_display_frequency = 4
teams = ["Canadiens"]
time_format = "12h"

[preferences.goal_animations]
pref_team_only = true

[states]
intermission = ["scoreticker", "team_summary"]
off_day = ["team_summary", "clock"]
post_game = ["team_summary", "scoreticker", "clock"]
scheduled = ["team_summary", "scoreticker", "clock"]

It requires a library like https://github.com/hukkin/tomli to use it which makes it really straight forward.