Merge branch 'dev'

* dev:
  disabled logging filter
  activated jersey logging filter
  removed auth annotation for GET methods
  fixed get measurement by id
  catch IAE for invalid ObjectIDs
  throw 404 for measurements that are not in the track
  throw 404 for invalid measurement identifier
  measurement encoding/decoding
  add created measurements to track
  renamed identifier property
  add track/user to created measurements
  fixed endless recursion due incorrect method call
  save optional track in measurements
  do not save id/created/modified for measurement values
  additional validation for measurements
  fixed incorrect constant
  renamed identifier property
  added local GeoJSON geometry schema
Merge branch 'dev'

* dev:
  test data creation script
  changed encoding of measurement values (fixes #25)
  removed fixme
  encode error for invalid created responses
  validate schema files while building
  only encode references to other entities
  updated schemas with common definitions
  multibinding dependency for rest module
  load schema files with guice
  root schema
  root schema
  renamed schema factory
Merge branch 'dev'

* dev:
  added name/modified to track list (fixes #26)
  changed mail address
  fixed NPE for group members resource
  sorted constants
  path constants
  seperate schema prefix
  name and description for tracks
  possibility to disable validation
  merged redundant code
  removed schemata from providers
  moved schema validation to filter
  some refactorings
  fixed test data script
Merge branch 'dev'

* dev: (38 commits)
  added name & description to creation script
  removed obsolete json dependencies
  ported schema validation tests to jackson
  ported integration test to jackson
  fixed measurement parsing
  fixed measurement parsing
  do not encode null names/descriptions
  do not encode null names
  return 400 for invalid json
  marked servlet-api as provided
  fixed error encoding
  fixed tracks encoding
  fixed sensor href
  added measurements ref
  JsonNodeProvider
  fixed geojson tests
  adjusted measurement encoder
  adjusted encoder return type
  adjusted GeoJSON coder test
  adjusted provider module
  ...
Merge branch 'dev'

* dev:
  added travis configuration
Merge branch 'dev'

* dev:
  Update README.md
Merge branch 'dev'

* dev:
  allow multiple integration tests
  formatting
Merge branch 'dev'

* dev:
  downgraded to jetty 7
Merge branch 'dev'

* dev: (22 commits)
  global statistics (fixes #12)
  statistics of users
  wrong variable usage
  keep track of aggregated tracks and users
  statistics of a track (fixes #13)
  statistics resource
  manual 2dsphere index
  missing annotations
  corrected $matches to $match
  statistics encoders
  statistics providers
  statistics service
  additional json constants
  statistics schema
  moved classes to statistics package
  implemented statistics dao
  measurement count is a long
  made mongo driver a direct dependency
  added indexes
  count statistics
  ...
Merge branch 'dev'

* dev:
  removed context.xml
Merge branch 'dev'

* dev:
  added unit of phenomenons (fixes #27)
Merge branch 'dev'

* dev:
  fixed invalid URIs
  pagination for all resources (closes #33)
  pages are 1 based; show only relevant links
  long entity count
  filter to insert RFC5988 compliant link headers
  pagination API
  adjusted creation script
  manual, cached reference handling for phenomenons, users and sensors
  invalidate cache on user change
  update modified time while adding measurments to track
  entity caches
  validate measurment values
  use UTC as default time
  more lazy loading
  measurement validation
  do not load tracks to add measurements
  removed href for track measurements
  disable response validation
  SLF4J configuration for morphia
  phenomenon statistics
Merge branch 'dev'

* dev:
  404 for users that are not friends
  configuration options for input/output validation
  removed unnecessary factory bindings
  compared wrong media type
  Fixed #36: Incorrect removal of friends
  more efficient user removal
  cleaned statistics dao dependencies
  remove user references on delete
  delete track references on measurements
  added todos for #35
  seperated encoders and decoders
  do not store measurement refs in track
  bulk upload completed Fixes #30
Merge branch 'dev'

* dev:
  link to base user URI in friend listings
  link to base group URI in group listings
  use UserReference for group and friend methods
  group members are saved in users instead of groups
  refactored DAO's
  removed obsolete methods
  friends in creation script
  users can not be friends of them self
Merge branch 'dev'

* dev:
  corrected bulk upload
  renamed variable
  removal of track references
Merge branch 'dev'

* dev:
  fixed track decoding
  replaced measurements with features for bulk upload
Merge branch 'dev'

* dev:
  added unit for measurement values (closes #27)
  fixed NPE with missing Content-Type header
Merge branch 'dev'

* dev:
  Fixed unintended recursion (closes #45)
  fixed group creation validation
Merge branch 'dev'

* closes #11
* closes #10
* closes #32

* dev: (26 commits)
  group activities
  fixed incorrect entity subclass intantiation
  activities resource
  implemented getMember
  implemented get friend
  implemented get friends
  added friends attribute to user
  user references instead of objects for queries
  implemented getMembers
  do not receive members if querying groups
  added MongoDB dependency to DAOs
  refactored entities
  removed subscription classes
  removed builder pattern from interfaces
  base interfaces (without relations) for entities
  return the right track
  saving of activity information
  guice binding of schemas/providers/encoders
  activity/activities schema
  encoders and providers
  ...
Merge branch 'dev'

* dev:
  small fix