Fix off-by-one effect of number of attempts.

This makes the showHints work properly.

.
Provide better solution to the numOfAttempts issue

Insures that the number of attempts defined in the environment is correct.
It is the sum of the number of incorrect attempts, the number of correct attempts
and the number of ungraded attempts (which is 1 or 0 depending upon whether an
answer has been submitted).
The calculation is done in PG.pm
Merge pull request #23 from mgage/release/2.6

Fix off by one bug in number of attempts