@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
Fix streaming Content-Length test
 First what you expect, second what you got (thank you @patriciomacadden)
Mention use of `:public_folder` in warning message
Optimize 400 and 500 images with ImageOptim
Merge pull request #795 from francisgo/patch-1

Optimize 400 and 500 images with ImageOptim
Snake-Case  ShowExceptions file
Merge pull request #796 from vipulnsward/snake_case

Snake-Case  ShowExceptions file
allow jruby-head to fail
Fix ruby and shell snippets in README.fr.md
Fix ruby or shell syntax in README.md