Merge pull request #1 from ch41rmn/master

OSX compatibility
Add transparent bzip2, gzip, and xz decompression
Add option to process CSV data
Fix typo
Add -M option
Add GNUTERM variable support

Permits reading a user's $GNUTERM environment variable to,
for example, use the wxt terminal by default instead of x11.
Rename -g option to -G
Add -g PATTERN option
Add jpeg output
Add JPG/SVG output, rework -e -p into -o

Plus a much improved README.md.
Update copyright
Permit enhanced terminal usage
Update README
Use 'reread' not 'replot;reread'

Only the former is required, and it should behave a
bit more nicely than the latter for complicated plots.
Include pause in -s output
Make ShellCheck happier
Remove -r (raise) option.

This can be accomplished with $GNUTERM, and the default raising
behavior is exactly what -r accomplishes if supplied.
Remove broken -S option
Add idea TODO
Isolated enhanced terminals into -e