Add 2 New Email Alert Frequency Flavors: Weekly and Bi-Weekly

I'm going to label the last option "Every two weeks" to avoid the ambiguity.

That makes sense!

I have code checked in for this issue on the
'tseaver-1132888-new_digest_frequencies' branch of the 'karl'
package.

Once deployed, we will need to update the crontab entires to run
extra digest passes, for instance, from the current::

    11 */6 * * * $KARLSERVE digest >> $LOGS/digest.log 2>&1

to::

    11 */6 * * * $KARLSERVE digest daily >> $LOGS/digest.log 2>&1
    * * * * * sun $KARLSERVE digest weekly >> $LOGS/digest.log 2>&1
    * * * * * sun $KARLSERVE digest biweekly >> $LOGS/digest.log 2>&1

It looks as though we need to make changes to the 'karlserve
digest' bit to pass through the frequency, too (it bypasses
the script in the 'karl' packge).

Note to self:

  Merging this issue's branch with the 'tseaver-1122345-deconflict_profile_pending_alerts'
  branch is going to be messy.

Staging works ok when you use blog posts instead of wiki pages, so Nat is able to test this once the tseaver-1132888-new_digest_frequencies-m125 (or tseaver-1132888-new_digest_frequencies) branch gets merged.

On osfkarl10, change crontab for the digest from::

------------ %< -------------------------
11 */6 * * * $KARLSERVE digest >> $LOGS/digest.log 2>&1
------------ %< -------------------------

to:

------------ %< -------------------------
11 */6 * * * $KARLSERVE digest --frequency daily >> $LOGS/digest.log 2>&1
* * * * * sun $KARLSERVE digest weekly >> $LOGS/digest.log 2>&1
* * * * * sun expr `date +\%W` \% 2 > /dev/null || $KARLSERVE digest biweekly >> $LOGS/digest.log 2>&1
------------ %< -------------------------

Also, add the 'BASH_ENV=/etc/bash/bashrc' at the top of each appserver's
crontab.

Released with karl 3.108 and pushed to OSF production (including the crontab change).

Nat, did you get an unexpected notification for your every-other-week subscription yesterday?