Fixes unhandled rejection in clasp logs

[campionfellin]

Does this by catching the error and logging an appropriate message for the user.

The error that it catches looks like:

{ Error: 8 RESOURCE_EXHAUSTED: Insufficient tokens for quota 'logging.googleapis.com/read_requests' and limit 'ReadRequestsPerMinutePerUser' of s
ervice 'logging.googleapis.com' for consumer 'project_number:xxxxxxxx'.
    at new createStatusError (/Users/campionfellin/Desktop/gcp-work/clasp/node_modules/grpc/src/client.js:64:15)
    at /Users/campionfellin/Desktop/gcp-work/clasp/node_modules/grpc/src/client.js:583:15
  code: 8,
  metadata:
   Metadata {
     _internal_repr:
      { 'google.rpc.help-bin': [Array],

My guess is that this error comes about because StackDriver logging takes a few minutes to get all set up. This PR catches that error and tells the user to try again.

I also noticed another severity level of NOTICE and so added that as well.

Signed-off-by: campionfellin campionfellin@gmail.com

Closes #128

• npm run test succeeds.
• Appropriate changes to README are included in PR.

[coveralls]

Pull Request Test Coverage Report for Build 88

• 0 of 0 (NaN%) changed or added relevant lines in 0 files are covered.
• 166 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.01%) to 10.549%

---

Files with Coverage Reduction	New Missed Lines	%
index.js	166	7.93%

Totals
Change from base Build 86:	-0.01%
Covered Lines:	93
Relevant Lines:	659

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💛 - Coveralls

[grant]

(We should add trailing-comma to our tslint to prevent 2 line diffs.)

[campionfellin]

Noted, will put that in the next PR.