Update: make proficiencies more descriptive

[rg-wood]

To emphasise that skills are about customising your character, this change proposes making the names more descriptive. For example, "Athletic" rather than "Athletics". Adjectives, rather than nouns.

So, a character sheet might look like:

Here is a summary of the changes:

Skill(s)	Descriptive Name
Acrobatics	Acrobatic
Athletics	Athletic
Animal Handling	?*
Arcana	Arcane*
Armed	Medium armour
Armoured	Medium armour
Deception	Deceptive
History	Learned*
Intimidation	Intimidating
Investigative	Inquisitive*
Insight	Insightful
Lightly Armoured	Light armour
Martial	Martial weapons
Medicine	Healing*
Performance	Talented*
Persuasion	Persuasive
Religion	Religious
Sleight	Tricky
Stealth	Stealthy
Survival + Nature	Wild*

*I'm not sure about these names, open to suggestions.

[rg-wood]

This approach has a number of benefits:

1. Collect the various rules for proficiency (weapons, armour, etc.) in one place.
2. Vastly simplify Backgrounds and Classes, allowing us to put all proficiencies into the level tables.

[rg-wood]

Depends on rules for Tools.