Add search_by_name and search_by_birth_date and deprecate search
Check date is valid
fixed bad method error message
better error message for token missing or invalid
search birthdates without the year and remove trailing whitespaces
fix error when multiples of 10
added support for searching users by birthdate
removed 'search' method from interface
changed interface of search_by_date to take day, month and optional year as integers
accepts birth date parameter as YYYY-MM-DD or MM-DD and parses and validates it
Merge new features added to 2.1 into 2.2:
    - better error handling and missing token
    - support for searching users by birthdate