[Client][HatoholMonitoringView] add prototype displayUpdateTime
[Client][Base] add div for display last update time
[Client][WebUI] display last update time per page
[Client][Base] remobe trailing spaces
[Client][WebUI] move last update time display massage into top center
[Client][Base][i18n] use Django I18n
[Client][MoniteringView] use i18n for last update time message
[Client][i18n] generate po
[Client][WebUI][i18n] add translation for `Last update time:`
Merge pull request #667 from cosmo0920/display-last-update-time

[Client][WebUI] Display last update time