Fixes weird testing name conflict

This should close issue #130
From the outside test breaks because settings are not loaded

Ignore the test if settings has not correct data loaded
Updated CHANGELOG
Minor tweaks in docs
Bug fix when wrapping fields with args after fields

Currently we had to do:

    form.helper['weight'].wrap(AppendedText, "weight", "kg")

When it should be simply:

    form.helper['weight'].wrap(AppendedText, "kg")

Moving `LayoutSlice` to a separate module named `layout_slice`, to avoid
circular dependencies.
Pop "css_id" to stop it being added as a "css-id" attribute
Updating CHANGELOG and CONTRIBUTORS
Added tests for Tab css_id
Removed repeated contributor
Fixed an typo issue
fix: active class is added several times, and to several tabs
Removed ipdb left behind
Only raising Exception in |as_crispy_field when DEBUG set to True
Bumping version to 1.2.5

Hotfix for not breaking sentry account tab
Merge branch 'master' of github.com:maraujop/django-crispy-forms
Access keys() for both dict and RequesContext
Merge branch 'patch-1' of git://github.com/mozillazg/django-crispy-forms into dev
Merge branch 'fix_tab_active' of git://github.com/chrisv2/django-crispy-forms into dev

Conflicts:
	crispy_forms/tests/tests.py
Updating CHANGELOG and CONTRIBUTORS
Bumping version to 1.2.6