Resolving most of notice and warning error

As stated in issue #21 MailWatch shoud report no error when running; thi is the first batch of correction to make it works in this way
Update functions.php
MSRE - Tidy up a little, fix "and" processing

If any part of an "and" section is missing then the whole "and" section
will be now be ignored
Merge branch 'master' of https://github.com/mailwatch/1.2.0
MSRE - fix typo
Merge pull request #66 from philrandal/master

MSRE - Properly handle non-existent $_POST variables, fix "and" handling