@mongrelion’s spanish README improvements

Instalá el gem y corré la aplicación con → Instalar la gema y correr la aplicación con
Podés verla en http://localhost:4567 → Ver en http://localhost:4567
Merge pull request #784 from somu/patch-1

@mongrelion’s spanish README improvements
:traps setting (on by default)
Merge pull request #785 from somu/traps-setting

:traps setting (on by default)
Don’t delete Content-Length if streaming
Test added
#send_file indifferent :status option
Merge pull request #786 from somu/streaming-content-length-fix

Don’t delete Content-Length if streaming
Use #Integer (thank you, @rkh)
Merge pull request #787 from somu/static-send-file-fix

#send_file indifferent :status option
Merge pull request #3 from sinatra/master

Update master branch