US03: Points System

[takouhai]

As a normal Slack user, I wish to give out points to users to be able to reward them for their help.

Acceptance criteria

• When I add a predetermined emoji next to another user’s name in chat, I should be able to award points to a another user.
• When I add a predetermined emoji next to multiple usernames, I should be able to award each of them with a point from my reserve.
• When I message the bot privately with an idea for a reward, I should be able to add an award through a short conversation for other users to redeem it.
• When I ask for a leaderboard, I should be able to see a list of users and how many points they’ve been awarded.

Design

@daniel: thanks for your help, @kattya! :pisco:
@bot [PM @daniel]: You just gave @kattya some :pisco:! You have 4 more shots to give out today.
@bot [PM @kattya]: @daniel just gave you some :pisco:! Enjoy it! :wink:

@daniel: @bot points leaderboard 
@bot: Here’s the points leaderboard so far:
Kattya - 3
Deiby - 2
Moises - 1 

// @moises already gave out the maximum amount of points today
@moises: @daniel mafia :pisco:
@bot [PM @moises]: You’re out of :pisco:! Wait until tomorrow to give out some more. :grin: