adds redirectTo method

Adds method `redirectTo` which is a shortcut for `redirect(urlfor(..))`

Helps making the code more readable by encapsulating a common pattern.
fixed phpdoc
replace newline instead of '\n'
add PHP 5.6 to .travis.yml
allow passing array of methods to Slim\Route::via() and Slim\Route::appendHttpMethods()

(cherry picked from commit 86654ba38ffa5f9c45422d8e8268a9698080c182)
Merge pull request #886 from sasezaki/patch-2

add PHP 5.6 to .travis.yml
Merge pull request #879 from mnlg/replace-newline

replace newline instead of '\n'
Merge pull request #856 from maldoinc/patch-1

adds redirectTo method
Merge pull request #2 from codeguy/master

Merge upstream