#34 applying  simple_format to history#show view
almost done except printing title
notification model added.
send notifications if mentioned
create notifications showing page
date showing added.
notifications unread/all view update.
Notification Unread/read feature added.
Merge branch 'master' of https://github.com/DonutWorks/ToDo.nut into rft/issue-45
#45 using ActiveModelSerializer
make projects and histories link
refactoring referenced projects and histories in profile page
refactoring profile page using has_many method
#45 serializer
reference library added.
library comment added.
not found bug fixed.
match parameter passing added.
add replace bang method, history_helper refactored.
fixed todo reference bug (regex), history association code is using ReferenceCheck now