Added support for flac greater than 1.2.1

[ ADDED ]  Check for flac 1.2.2 or greater to allow script to log
files that cannot be processed (ReplayGain-wise) when the sample
rate of said FLAC files are greater than 48kHz

[ FIXED ]  Typos in documentation/logging

[ FIXED ]  The skipped message is now yellow (NOT red) to indicate
less severity

[ ENHANCEMENT ]  Improve various functions
Improvements to script comment readability

[ ENHANCEMENT ]  Improved comment title readability, making the
header comments much more consistent with other projects
User interruption has its own exit code

[ ENHANCEMENT ]  Exit code for user interruption (SIGINT) is now
'130' for each operation

[ ENHANCEMENT ]  Comment cleanup and various comment additions
Revamped logging messages to STDOUT and STDERR

[ ENHANCEMENT ]  Simplified how messages are displayed to STDOUT
and/or STDERR

[ ENHANCEMENT ]  Colors are now included in messages printed to
STDOUT and/or STDERR

[ ENHANCEMENT ]  Cleaned up messages detailing missing programs

[ ENHANCEMENT ]  Various tweaks
Enforce a non-zero integer for '-j, --jobs'

[ FIXED ]  Do not allow '0' for '-j, --jobs' argument
Implemented a spinner to show progress

[ ADDED ]  A spinner is now shown on each operation to help the user
understand something is happening in the background for longer
operations

[ ADDED ]  Documentation on non-zero integer for '-j, --jobs'
argument
Various UI fixes/enhancements

[ FIXED ]  Spinner is now killed correctly before UI changes

[ ENHANCEMENT ]  Don't indent log file locations

[ ENHANCEMENT ]  Processing files [ ok ] message now in line with
top and bottom banner
Use more sane integer range: [[:digit:]]

[ ENHANCEMENT ]  POSIX integer range: [[:digit:]]

[ ENHANCEMENT ]  UI tweak