Recently from the server suggestions, many people have been slightly upset
that the only reaction emoji considered for adding to the quotes board is
the default star emoji.

Some members have suggested specific additional emojis to be considered,
others suggested that the star emoji should have a weight of 1.0 while
the rest of the emojis should have a weight of 0.5. While both solutions
can work, all emojis can have a custom weight for the purpose of
customizability.

Introduce a scoring concept for each emoji, configurable for each
particular one, and provide the ability to set a default value if an emoji
is not defined in the configuration file.

For those who are wondering, _any_ kind of emoji that Discord can handle
is able to be added in the configuration, including custom emojis in the
server.  JDA can keep track of those.

For adding a unicode emoji, the actual unicode value has to be provided,
like it has been done in "config.json.template".

For adding a guild emoji, a "code" for the emoji has to be provided, for
instance:

    youtube:1464573182206804010

Which stands for the friendly name of the emoji, a colon right after, and
finally the ID of the custom emoji.

The "config.json.template" is _NOT_ exhaustive, more emojis have to be
added and some others removed according to preference.

Signed-off-by: Chris Sdogkos <work@chris-sdogkos.com>