#3 Tab Size, Font, Font Size in Source View

[Jeremy Clifton]

Added the ability to specify the the tab size, font, and font size for the
source view via <param> tags. The new parameters are TABSIZE, FONT,
and FONTSIZE.

Changes:
1. KafenioPanelConfiguration.java - Added vars for tabSize, sourceFont,
and sourceFontSize as well as getters/setters for these vars. Default
values: tabSize = 4; sourceFont = 'Monospaced'; sourceFontSize = 12.

2. KafenioApplet.java - Added calls to set the config values for tabSize,
sourceFont, and sourceFontSize based on the applet values, or use the
default values if none are given.

3. KafenioPanel.java - Added setTabs method for setting the tab size.
Added code to the KafenioPanel constructor to set the tab size, font, and
font size in srcPane.

4. Utils.java - Added an additional checkNullOrEmpty function that
converts the String value from getParameter to an integer and returns it
(for integer values for tabSize and fontSize).

[Jeremy Clifton]

Diffs for KafenioPanelConfiguration.java, KafenioApplet.java, KafenioPanel.java, and Utils.java