Detect constant leaks in individual examples

MSP-11130

`Metasploit::Framework::Spec::Constants::Each.configure!` will set up an
`after(:each)` callback that will fail the example if there are leaked
constants.  Leaked constants are cleaned up to prevent misattribution.
Ensure necessary cookies are present in OWA 2010 login response
Set proper Cookie header from built cookie string
Show more helpful vprint messages when login fails
Abort if 2013 desired but redirect didn't happen
Prevent calling match when there is no WWW-auth header
Fix issues reported by wchen-r7
Updated rescue to catch other errors from the socket API
Fix value of X7C2P cookie and typo
Updated to module based feedback from wchen-r7
Metasploit::Framework::Spec::Constants cleaner

MSP-11130

Shared context will calls `Metasploit::Framework::Spec::Constants.clean
after each example.
Fix a simple typo
Rename shared example file to match name

MSP-11130
Force msfconsole to use stdlib's readline with -L
Updated get_once for get_once undefined method  and EOFError
Clean up leaked constants

MSP-11130
Changed upper XXX to lower XXX.
Add module first version
Fix readline by mucking with load path
Better explanations