Remove Animation section whose content can be found on the wiki

...ocs/chapter/user/11_Animation/10_GeneralPresentation.adoc

src/docs/chapter/user/11_Animation/12_Animation.adoc

...r/user/11_Animation/13_Colours_of_enabled_operations.adoc

...apter/user/11_Animation/Controlling_ProB_Preferences.adoc

...cs/chapter/user/11_Animation/Tutorial_Animation_Tips.adoc

src/docs/chapter/user/11_Animation/Tutorial_First_Step.adoc

...docs/chapter/user/11_Animation/Tutorial_Setup_Phases.adoc

...Tutorial_Understanding_the_Complexity_of_B_Animation.adoc