Create new auCDtect skip lossy configuration

[ ADDED ]        Option:  Skip FLAC files that have the tag:
                 'MASTERING=Lossy' when analyzing with auCDtect
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[ ENHANCEMENT ]  Small readability changes to configuration settings
Implement auCDtect skip lossy logic

[ ADDED ]        The ability to skip FLAC files that already have a
                 value of 'Lossy' for the 'MASTERING' tag field
[ ADDED ]        New status of 'SKIPPED' in error logs detailing a
                 FLAC may not be corrupt, and was skipped for one
                 reason or another
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[ ENHANCEMENT ]  Configuration tweaks
Small fix to auCDtect UI

[ FIXED ]  Failed FLAC file not printing out FLAC filename if the
           FLAC file was found to be not real
Add '-e, --extract-artwork' operation

[ ADDED ]  New operation '-e, --extract-artwork'.  By default, this
           operation extracts any and all types of artwork embedded
           inside FLAC files into a directory with with the same name
           as the FLAC file (with a unique name appended).  This is
           useful to save all the artwork before removing it via the
           '-p, --prune' operation
New Configuration option for extracted artwork

[ ADDED ]        New configuration options: 'artwork_location' to allow
                 a user-defined location for storing extracted artwork
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[ ENHANCEMENT ]  Configuration comment tweaks
Use a more accurate 'sleep' command

[ ENHANCEMENT ]  Replace `sleep` with `read -t[num]` to get rid of
                 the dependency on `sleep`
Simplify some 'for' loops

[ ENHANCEMENT ]  Use BASHISM '{<num>..<num>}' to simplify C-style
                 for loops where possible
Enforce succession when determining percentage

[ FIXED ]  When determing the percent of a current operation, check
           if the value obtained is an integer.  If not, set it to
           '0' so the math doesn't fail.  This seems to only happen
           if any file (or path) contains a '%', which causes extra
           line breaks (newlines) causing the first couple of
           percent operations to return a non-integer value
Added documentation on '-e, --extract-artwork'

[ ADDED ]  Added documentation '-h, --help' for the new argument,
           '-e, --extract-artwork'
Fix wrong variable for extracting artwork logging

[ FIXED ]  Wrong variable used for extracting artwork error logs:
           prune_errors -> extract_artwork_errors
Added check for 'mkdir' command

[ ADDED ]  Added check for 'mkdir', which is a part of Coreutils,
           resulting in no additional dependencies
Small documentation fix

[ FIXED ]  Removed redundant 'type'