Add new grid submission script

Add grid-submit. This is a general purpose submission script that can replace the others at some point (now?). Closes #68 (closed).

Usage

(tdd) tdd $ grid-submit -h
usage: grid-submit [-h] [options] MODE

    Submit dumper jobs to the grid! This script will ask you to commit your changes.
    Specify a running MODE (below) and then optionally overwrite the mode's defaults
    using the optional flags. You are encoraged to use the -t argument to tag your 
    submission.

Options:
 -s script : Executable to be run (e.g. dump-single-btag)
 -c config : Path to the config file to use for the jobs
 -i file   : File listing input samples, will override the default list
 -t tag    : Tag the current code state using the supplied string
 -f        : Force, don't require changes to be committed
 -a        : Run a test job using only one file per dataset
 -d        : Dry run, don't submit anything or make a tarball, but build the
             submit directory

Modes:
 upgrade-HI     => ca-dump-upgrade-HI -c upgrade-HI.json
 trigger        => ca-dump-trigger-btag -c trigger.json
 retag          => ca-dump-retag -c EMPFlow.json
 upgrade        => ca-dump-upgrade -c upgrade.json
 trigger-wp     => ca-dump-trigger-workingpoints -c trigger_wp.json
 single-btag    => dump-single-btag -c EMPFlow.json

For basic usage it will probably sufficient just to specify a MODE positional argument. The default script, config, and inputs file can be overwritten with optional arguments.

Other improvements

• Argument parsing robustness is improved (optional arguments after positional will complain).
• Better feedback if things are not setup correctly
• Inputs go in different files under grid/inputs

Tests

We should probably ask users to confirm that they can use the new script before removing the old ones

• single-btag
• retag
• trigger
• trigger-wp
• upgrade
• upgrade-HI