Tweaked .gitignore file and Gemfile
Refactored and significantly cleaned up request handling. Much of this needs to be unit tested. Tests are coming soon, promise.
Remove unnecessary whitespace from SNMP4EM::Manager
Renamed SNMP4EM::CommonRequests to SNMP4EM::SNMPCommonRequests to match SNMP4EM::SNMPv2Requests
Refactored the generation of SNMP ID values
Refactored the cancelling of a request's timeout timer
Tweaked Manager's fetching of request when receiving a response