#1956 - Escape LIKE queries (for _ and %).
In MySQL queries, _ and % characters are treated as wildcards (similar to ? and *, respectively).
- Added escape_for_like function to MY_Database.php
- Added unit test to Database_Test
- Corrected the five unescaped instances in the code using this function.
Merge pull request #100 from shadlaws/fix_1956

#1956 - Escape LIKE queries (for _ and %).