attic: remove all files which required EclipseGridParser

since the attic is the place for bits to rot silently, I doubt that
this code would have been of much contemporary use anyway. Even if it
could be made to compile, porting it to opm-parser would hardly be
worth the effort. If you are nostalgic and want to see how things were
done in the olden days, use `git show $COMMIT` or `git log --stat` or
`git log -p` and search for "EclipseGridParser"...
remove EclipseGridParser compatibility methods from all classes
remove the EclipseGridParser class

RIP!
rename all "newParserDeck" objects to "deck"

The "new" parser is now "the" parser...
remove the `table_t` type

that was an artifact only required for the old parser