Fix the Infinite AIPs feature

[jrwdunham]

Fixes #118
Fixes #114
Fixes #117

• Adds exponential backoff to the polling which detects the availability of the "approve transfer" select.
• Makes normalization configurable in infinite-aips.feature.

[jrwdunham]

@jhsimpson I have tested this by running the appropriate behave command on our bcadmin server against the http://158.69.86.69:81/ test machine. Note the new --tags=decision.id.not-norm in the behave command below (which, aside from the false password, should work on our test infra):

$ behave \
      --tags=infinite-aips \
      --tags=decision.id.not-norm \
      --no-skipped \
      --no-logcapture \
      -D runtime_supplied_transfer_path='~/test' \
      -D driver_name=Firefox \
      -D am_url=http://158.69.86.69:81/ \
      -D am_password=somepassword \
      -D am_version=1.7 \
      -D home=archivematica