fix file-input: remove transclude

Before we need to create the input file when using the directive
By moving the input file from the transclude to the template, the user doesn't have to create the input anymore
chore demo: remove transclude
refactor file-input: Add "change" and "value" parameters

"Change" parameter as callback to return the dom input to the function
"value" parameter to handle dynamic values and automatically set the value if needed to
fix file-input: Fix indentation to the Allman style
docs file-input: Add comments for better comprehension of the value attribute
refactor file-input: add "newValue" and "oldValue" to the parameters returned in the change callback

Before, we are using a non-conform way to pass values in callback.
By adding brackets in the callback, we switch to the angular-way and return two more values : the new input value and the old.
Merge pull request #8 from lumapps/fix/file-input

Fix/file input