Remove parentheses and make more Ruby standard
Make filename in the initializer optional

 since it is not used in all instance methods
General code cleanup
Remove deprecated Digest::Digest
Base file is commonly needed

... so raise exception immediately if not provided during object initialization
Ensure request is set to something so it can be tested later
Code clean up
Simplify URI sign
Simplify code
Bugfix: misspelled true "ture"
Use natural ruby return
Reformat array to make more readable
Code spacing changes
Use natural Ruby return
Remove unnecessary initialize block
Cleanup code
Bugfix: string append did nothing
Simplify return code
Simplify return code
Simplify return code