Automatically reload conf without restarting server

*** NEW FEATURES ****

upgrade async, express, mongodb dependencies in package.json
add nodemon dependencies to reload conf automatically
start server.js with nodemon instead of node
conf file is only in front/conf directory

##**** FIXES ****

correction of begin date and end date for code review search
replace old cerberus logo with the new one
change path of jenkinsdeploy api and simplify process to get correct number of deploys
modify design of index.html
remove unused conf, modify date format for better understanding