add @ as a keyword when recording event

[masukomi]

hey <people> + <tags> @ <timestamp>
# or 
hey <people> @ <timestamp>

the text after @ should be considered a timestamp and should be in the form of HH:MM but it should assume 24hr time. So, while we should accept 2:31 we should assume it's 2 in the morning not the afternoon. 02:31 would, also be 2:31 AM.

IF the timestamp is parseable as a timestamp then it should be used as the timestamp on the event. IF NOT then NOTHING should be created and it should respond with

Unable to parse your timestamp. No entries have been created. 
Timestamps must be in the HH:MM format in 24hr / Military time.