- Improved doc

- Simplified the code by removing the use of the Lua Activation interface

- Added German Translation
- Reworked English translation

Speechcraft boost is replaced with personality boost to remove trainers constraints.

Removed 'limite skill difference' setting.
Max speechcraft difference default to 100: No limit.

- Restore personality during barter to prevent cumulative boost with mercantile
- Fixed speechcraft reduced under NPC default value

Improved and fixed docs

Don't override Arrille level as every player will usually increase his disposition and thus already get good prices

- Removed 'Max speechcraft difference with player' setting.
- Fixed mercantile boost not applied if there is no personality boost.
- Allow mercantile decrease.