Created pdo-refactor branch, started conversion
Merge changes from branch 'master' into pdo-refactor to capture changes.
Added pdo_test.php to test making PDO connections to MySQL

In pdo_test, only the currently active line
```
$stmt = $dbh->query('SELECT * FROM Apprentices');
```
succesfully selects the correct data from the db, and returns the array of results.

The other pairs of ```$stmt = $dbh->prepare(``` and ```$stmt->bindValue(``` statements,
as well as the ```$dbh->query``` statement that uses the $tableName variable, all attempt
to pass the explicit SQL string contained in the single quotes.
Corrected bindValue statement and variable assignments
Refactored select.php for PDO
Refactored insert.php for PDO db connection
Updated TUTORIAL with php5enmod instructions for PDO
Refactored create_db for PDO db interaction
Added close connection statements to insert and pdo_test
Refactored create_table for PDO db connection
Refactored alter_table for PDO db connection
Updated README for setting up db cred files
Deleted pdo_test.php, as only used temporarily
Merge pull request #1 from AmundsenJunior/pdo-refactor

Merge pdo-refactor branch into master