scope launch script: Fix shellcheck linter warnings
scope launch script: Fix shellcheck linter warnings

By far the majority of these were variables which were not quoted.
While, yes, right now we can guarentee most of these variables will never contain spaces,
this could someday change and applying quoting as a universal rule prevents future mistakes.

The ARGS="$@" -> "$*" change is purely stylistic and mainly is used to indicate the intent that
we actually wanted to concatenate all the args by spaces, not keep them seperated as "$@" would
in many situations, but not this one.

Several warnings remain, in places where we intentionally want to split a variable on whitespace,
or otherwise do what shellcheck is warning us against.

Of note is shellcheck warning SC2166, which says to prefer [ foo ] || [ bar ] over [ foo -o bar ]
as the -a and -o flags have differing behaviour on some systems.
I've opted to keep these for now, since the version check test command would need to be replaced by
a LOT of subshells to achieve the same effect, which feels dirtier.

paulbellamy/scope,paulbellamy/scope,alban/scope,kinvolk/scope,paulbellamy/scope,alban/scope,weaveworks/scope,weaveworks/scope,kinvolk/scope,alban/scope,alban/scope,weaveworks/scope,weaveworks/scope,kinvolk/scope,kinvolk/scope,paulbellamy/scope,paulbellamy/scope,kinvolk/scope,alban/scope,alban/scope,weaveworks/scope,paulbellamy/scope,kinvolk/scope,weaveworks/scope