Remove Values

Cf. #28
Migration to remove Value.

Fix #28
Forgot one Value
Internal cosmetic adjustement
Typo
Merge branch 'hugo' of github.com:Neamar/kingdoms
Typo
Added:
	get_set_value for PendingEvent and PendingEventValue
	tests for these functionalities
Modified:
	tests for templating

param must not be modified anymore (use param.set_value() instead)
Merge branch 'BOM' of github.com:Neamar/kingdoms
Add migration for trigger slug
Update test for slugs
add log in page