Fix script area issue

[monicagiraldochica]

Sorry, i deleted the branch by mistake. This is the same pull request as previously.

The app was re-writing any command that the user might type under the SBATCH (or other) heather. I fixed it so that when the script area is re-written, it only re-writes the heather (SBATCH lines) and not any additional commands.

[mnakao]

Thank you very much for the pull request.
I tested the change and found that it does not work correctly when the script section contains lines other than #! and #SBATCH.
For example, if the script section in sample_apps/Slurm/form.yml is defined as follows, the final mpirun line is not visible:

script: |
  #!/bin/bash
  #SBATCH -p #{partition}
  #SBATCH -n #{cores_memory_1}
  #SBATCH --mem #{cores_memory_2}G
  #SBATCH -t #{time_1}:#{time_2}:00
  #SBATCH --array=#{array_1}-#{array_2}
  #SBATCH --mail-user=#{email}
  #SBATCH --mail-type=#{mail_option}

  mpirun -np 1 ./a.out

In addition, Open Composer generates lines that do not start with #! or #SBATCH as well, but the current implementation does not seem to handle those cases.