Update README files for proper description of states

With Ansible there is no add or remove user, there is only ensure presence
or absence of users. The descriptions have been adapted to make sure that
the description is correct now.

README-group.md

@@ -4,7 +4,7 @@ Group module
 Description
 -----------
 
-The group module allows to add, remove, enable, disable, unlock und undelete groups.
+The group module allows to ensure presence and absence of groups and members of groups.
 
 The group module is as compatible as possible to the Ansible upstream `ipa_group` module, but addtionally offers to add users to a group and also to remove users from a group.
 

README-host.md

@@ -4,7 +4,7 @@ Host module
 Description
 -----------
 
-The host module allows to add, remove, and disable hosts.
+The host module allows to ensure presence, absence and disablement of hosts.
 
 The host module is as compatible as possible to the Ansible upstream `ipa_host` module, but addtionally offers to disable hosts.
 

README-topology.md

@@ -4,7 +4,7 @@ Topology modules
 Description
 -----------
 
-These modules allow to manage the topology. That means that topology segments can be added, removed and reinitialized. Also it is possible to verify topology suffixes.
+These modules allow to manage the topology. That means that it can made sure that topology segments are present, absent or reinitialized. Also it is possible to verify topology suffixes.
 
 
 Features

README-user.md

@@ -4,7 +4,7 @@ User module
 Description
 -----------
 
-The user module allows to add, remove, enable, disable, unlock und undelete users.
+The user module allows to ensure presence, absence, disablement, unlocking and undeletion of users.
 
 The user module is as compatible as possible to the Ansible upstream `ipa_user` module, but addtionally offers to preserve delete, enable, disable, unlock and undelete users.