issue #1405 -  params hash keys
- the `params` variable is converted into a HashWithIndifferentAccess
  object
- fixes #1405
Merge pull request #1470 from padrino/issue-1405-param-hash

#1405 params hash keys.  Fixes #1405
Skip the `:path_traversal` protection, fixes #1391.
Merge pull request #1472 from padrino/fix-incorrect-params2

Skip the `:path_traversal` protection, fixes #1391.