Instead of reading the files directly for --tla/ext-*-file, just add a
code snippet that does an import or importstr.
This makes relative imports work when the code-file path is not in the
current directory. It also makes the import lazy so if the arg/var is
not referenced, the file does not have to exist.
Fixes: google/jsonnet#452
The imports in "_gen.go" were not used, compiled, or
apparently useful so remove.
The color field in the ErrorFormatter was never set
to true and never used. This brought in many unused
dependencies including x/sys/unix that aren't ever
used. Move the color dependencies to the jsonnet main
package and set the colorized output there. Turn the
exported ErrorFormatter into an interface. In the future
it could be used to export JSON or HTML output.
Fixesgoogle/go-jsonnet#131
