In class SyncedSettings:
* added field contacts
* added setter and getter for field contacts
* added initialization of contacts to class constructor
In class Identities:
* changed collection type from Set to Map in order to enable retrieving identity by key identifier
* adapted change of collection type in add() method
* added getter getIdentityByKeyIdentifier()
* added javadoc for new and modified methods
new class SyncedSettingsTypeAdapter
In class ConfigSerializationTest:
* split tests for SyncedSettings and LocalSettings
* changed test for SyncedSettings to use new SyncedSettingsTypeAdapter
* changed URLs in contactTest to match the DropURL format
in class Identity:
* added annotation SerializedName("keys") to field primaryKeyPair
Adds Account equals test
Merge pull request #188 from thechauffeur/Add-Accounts-equals-test

Adds Account equals test.
Merge pull request #174 from f-porter/Issue172-add-contact-simplify-de-serialization

Issue172 add contact simplify de serialization
Added remove() method to config container classes to remove contained elements
Merge pull request #189 from f-porter/Issue175-Implement-remove-method

Issue175 implement remove method
added javadoc to class Account
added javadoc in class Accounts
added javadoc in class Contact
added javadoc in class Contacts
added javadoc in class DropServer
added javadoc in class DropServers
added javadoc in class Identity
added javadoc in class LocalSettings
added javadoc in class Settings
added javadoc in class StorageServer