[SalesForce] How to remove all translations from Translation Workbench

Here a sample file for deploying Translations (German) of some Standard and Custom Objects with all its fields:

<types>
    <members>Account</members>
    <members>Contact</members>
    <members>Case</members>
    <members>CustomerRequest__c</members>
    <name>CustomObject</name>
</types>

<types>
    <members>Account-de</members>
    <members>Contact-de</members>
    <members>Case-de</members>
    <members>CustomerRequest__c-de</members>
    <name>CustomObjectTranslation</name>
</types>

<version>34.0</version>

Here a sample file for deploying Translations (German) of Custom Applications, Custom Labels, Custom Buttons and Custom Tabs:

<types>
   <members>*</members>
   <name>CustomApplication</name>
</types>

<types>
   <members>*</members>
   <name>CustomLabels</name>
</types>

<types>
   <members>*</members>
   <name>CustomPageWebLink</name>
</types>

<types>
   <members>*</members>
   <name>CustomTab</name>
</types>

<types>
   <members>*</members>
    <name>Translations</name>
</types>

For custom objects that are part of a Managed Package this is done slightly different, because you have to override the values provided in the package:

1. Click Setup->Translation Workbench->Override
2. In the override screen, select the Managed Package that contains the field you want to relabel
3. Pick the Component that you want to relabel (in this case, Custom Field)
4. Pick the object that contains the field
5. Pick "Field Label" (or whichever aspect you want to override)
6. The rest is same as 'normal' fields

The reason that you only have to do this for 'English' is that the Managed Package's language is probably English and thus they have provided only the labels for that 1 language. So only 1 set of labels to override.