Default verbosity is too verbose, needs to be a tight summary

[chad-earthscope]

The default (minimum) verbosity is too verbose, containing at least three lines for each file. This validator should be able to run on thousands of files and millions of records and this level of output quickly becomes overwhelming. The validator also produces some header and footer bracketing:

**********xseed-validator STARTING validation**********
---------------------------------------------------------

...

----------------------------------------------------------
*xseed-validator COMPLETE - 11 record(s) processed in 11 file(s)*
****xseed-validator SUCCESSFULLY validated 11 file(s)****

All but the last two lines are useless and the copious asterisks are visual noise. Perhaps the intention was to create parsable output, which could be useful, but this could be achieved with much less noise.

The current verbosity levels should all be moved up one, e.g. default becomes -v, and -v becomes -vv, etc.

The default minimum verbosity should only include the filename and validation errors when they occur, i.e. no output for files that are valid, and the final status of all files with a file count.

[chad-earthscope]

The default minimum verbosity should only include the filename and validation errors when they occur, i.e. no output for files that are valid, and the final status of all files with a file count.

This may not have been clear enough, apologies, there should only be filenames printed at the lowest verbosity level when they have validation errors.

The lowest verbosity should level should be relatively quiet for any amount of input data if it's there are no validation errors. A simple summary of files and records checked is all that is needed.

[chad-earthscope]

Addressed in #13