Log the version of PSSA we import

[rkeithhill]

Given issues we've seen recently, it would be nice to have this info
in the log.

This will output:

2018-06-03 20:48:38.753 [VERBOSE] C:\Users\Keith\GitHub\rkeithhill\PowerShellEditorServices\src\PowerShellEditorServices\Analysis\AnalysisService.cs: In method 'EnumeratePSScriptAnalyzerCmdlets', line 362:
    The following cmdlets are available in the imported PSScriptAnalyzer module (version 1.16.1):
        Get-ScriptAnalyzerRule
        Invoke-Formatter
        Invoke-ScriptAnalyzer

[rkeithhill]

Heh, I was wondering if CmdletInfo had the Version property going all the way back to v3. Apparently, it doesn't. :-( Guess we can table this PR until v2 where we drop v3/4 support.

[rkeithhill]

Closing this in favor of PR #677