[BUG] Username is case-sensitive when logging into MC Administrator

[mgaffigan]

Describe the bug
Login to Mirth Connect Administrator fails if the case of the username doesn't match.

To Reproduce
Try to log in to MCA with different case on the letters.

Expected behavior
Login succeeds.

Actual behavior
Login fails with invalid username/password on Postgres, Derby, Oracle.
Login fails with "There was an error connecting to the server..." on SQL Server and MySQL.

Related
Original bug #5569
Summary table in #121

[mgaffigan]

Seems like on the case-insensitive database engines, the error on client side is:

java.lang.NullPointerException
       at com.mirth.connect.client.ui.components.tag.MirthTagField.<init>(MirthTagField.java:75)
       at com.mirth.connect.client.ui.ChannelPanel.initComponents(ChannelPanel.java:3374)
       at com.mirth.connect.client.ui.ChannelPanel.<init>(ChannelPanel.java:204)
       at com.mirth.connect.client.ui.Frame.setupFrame(Frame.java:562)
       at com.mirth.connect.client.ui.Mirth.<init>(Mirth.java:66)
       at com.mirth.connect.client.ui.LoginPanel$8.handleSuccess(LoginPanel.java:566)
       at com.mirth.connect.client.ui.LoginPanel$8.doInBackground(LoginPanel.java:455)
       at com.mirth.connect.client.ui.LoginPanel$8.doInBackground(LoginPanel.java:424)
       at javax.swing.SwingWorker$1.call(Unknown Source)
       at java.util.concurrent.FutureTask.run(Unknown Source)
       at javax.swing.SwingWorker.run(Unknown Source)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
       at java.lang.Thread.run(Unknown Source)