db
db get the db handler from MongoDB
save
save will commit the current state of the TimeEntry to the database.
duration
duration returns the time between this entry and the next.
find
find will return a single document. The query will use the provided _id.
search $config %options...
search will return an array of TimeEntry that fit the given %options.
%options can include the following:
query- 
This is the query syntax available via MongoDB::Collection.
 sort- 
If present, the results will be sorted via the hashref given by this option.
 limit- 
If present, the results will limited to the number provided.
 
last_entry
last_entry will return the last TimeEntry in the db.
TO_JSON
TO_JSON will return the entry as a JSON convertible hash.