SI-9279 Improve performance of bash runner script

In fbe897d16, the template for bash scripts (scala/scalac/etc) was
modified to fix processing of `-J`, `-bootcp`.

This involved looping through the argument array and filtering out
options like `-bootcp` that only influence the script, and shouldn't
be passed to the JVM.

However, the mechanism to do this uses an inefficient, erm,
"CanBuildFrom", and under the load of even a few hundred source
files takes half a second before the JVM starts. Throw 2000 files
at it, and you have to wait ten seconds!

This commit uses a more efficient array append operator. This requires
Bash 3 or above. Hopefully it is safe to presume this version these
days, it's been around for a decade.

Results:

```
% time ~/scala/2.11.6/bin/scalac -J-NOJVM abcdedfghijklmnopqrtsuvwxyv{1..2000} 2>&1
Unrecognized option: -NOJVM
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.

real	0m7.765s
user	0m7.734s
sys	0m0.028s

% time ./build/quick/bin/scalac -J-NOJVM abcdedfghijklmnopqrtsuvwxyv{1..2000} 2>&1
Unrecognized option: -NOJVM
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.

real	0m0.144s
user	0m0.124s
sys	0m0.022s

```

Thanks to Stephan Schmidt for pointing out the performance gulf.

0 files changed, 0 insertions, 0 deletions