another test of merging
added LatexHandler class, see LatexExample class for usage
Added line numbers to statements
latex now generated locally
cleanup latex handler, remove example
first attempt to display latex

- ExpressionListCellRenderer *should* turn Expressions into Components
containing LaTeX images, but it's not working.
- SubstitutionCellRenderer now extends DefaultListCellRenderer instead
of ExpressionListCellRenderer, until the latter calms down.
second attempt to display latex

- Now the ExpressionListCellRenderer creates JLabels holding Icons of
Images of the LaTeX.
- Still doesn't work. (Nothing is visible on the expression list on the
MainWindow.)
- Contains stdout messages for debugging purposes.
Revert "cleanup latex handler, remove example"

This reverts commit 7bad87d87c5fa137dde8102aac132c37aa6172c7.
make warnings go away
fixed bug where latex was being generated either remotely or not at all
labels now work on points, lines, rays, and circles; statements now in east pane, code cleaned up
removed debug output; adjusted LaTeX color display
Merge remote-tracking branch 'origin/latex-support' into latex-display

Conflicts:
	src/LatexExample.java
Merge branch 'master' into latex-display
Removed reference to ExpressionSelectionDialog.
Now properly renders the entire selected statement in yellow.
Removed unused import
Added new Statement class. No references yet.
ExpressionListCellRenderer now uses Statements instead of Expressions. (Breaks the build!)
ExpressionListModel now uses Statements instead of Expressions. (Breaks the build!)