Zero width (#4110)

Remove zero-width characters from the beginning and end of all parameters in all controller actions

* Add String#remove_zero_width_chars to remove all zero width unicode characters
* Add before action in ApplicationController to strip zero-width
characters from all parameters including child arrays and hashes.

Co-authored-by: Sumith Baddam <sumith.reddy2@gmail.com>

config/initializers/avalon.rb

@@ -1,3 +1,4 @@
+require 'string_additions'
 require 'avalon/errors'
 # Loads configuration information from the YAML file and then sets up the
 # dropbox