rename a property and a method for backward query

I will implement quries for backward with max_id and forward with since_id
Therefore, I renamed the property and method related with query to
prepare next query method, get_search_result_forward.
refactor storing and reading tweet status for max_id

Save only one file including all status instead of two files with json format
and read the file with json
write status by only one method instead of using multiple action by methods

For simple use, wtire status into one file and the method, write_status
, write all kind of status such as most recent id, most early id, etc
This implementation allows developer to ignore many different actions,
but increases littble bit more transaction during writing properties.
rename write_file to write_result for understanding more clear