fix environments updating global array

The environments plugin was changing `MergeDeep.NAME_FIELDS`, which is a global object. The reason was to avoid environments being filtered out from the change list if they only have a name field.
However, the environments plugin has it's own overriden sync method, and thus we can simply drop the whole filtering from that method.

Fixes #108

Author: gramatus

lib/plugins/environments.js

@@ -17,10 +17,6 @@ module.exports = class Environments extends Diffable {
               }
             })
         }
-
-        // Remove 'name' from filtering list so Environments with only a name defined are processed.
-        MergeDeep.NAME_FIELDS.splice(MergeDeep.NAME_FIELDS.indexOf('name'), 1)
-
     }
 
     async find() {
@@ -304,7 +300,7 @@ module.exports = class Environments extends Diffable {
               }
             }
           }
-          filteredEntries = filteredEntries.filter(entry => Object.keys(entry).filter(key => !MergeDeep.NAME_FIELDS.includes(key)).length !== 0)
+          // For environments, we want to keep the entries with only name defined.
 
           const changes = []