Standardize verbosity

[HalosGhost]

At the moment, if a user calls shaman with the -v or --verbose flag, the only difference will be that, if the cache is not found, an error will be printed.

The behavior for verbosity should be extended beyond just cache location, and should have well-defined and understandable behavior.

I am considering the following:

• -v will print all non-fatal error messages along with the string from the format specifier.
• -vv will print all status information throughout the execution (e.g., this would include setting curl_easy's verbosity flag).

Does anyone feel that it would be helpful to add another level of verbosity? If so, what should it include?

Does it make sense to add a corrolary flag -q|--quiet that will silence everything (e.g., it would not be too difficult to have shaman return part of the weather code to indicate some information about the current condition while printing nothing)?