PdeKeyListener.java: tab key behaves correctly if !editor.tabs.expand

If the `editor.tabs.expand` preference setting is set to `false` (tabs 
are *not* expanded to spaces), insert a tab character when the tab key 
is pressed. Previously nothing would be inserted.
type safety update..
Merge branch 'master' of https://github.com/processing/processing
Fixes #2656
Merge branch 'master' of https://github.com/processing/processing
Implemented elliptical arcs for PShapeSVG

Feature request #169
minor code changes
minor code updates to get rid of warnings..
removing warnings
more code cleanup
code cleanup
todo update
some stuff disabled for java tabs
more java tab stuff
fix build.xml for pdex
dialog for new tab and rename. Fixes #2431
Merge pull request #2607 from teddywing/insert-tab-char-on-tab-keypress-if-not-editor.tabs.expand

PdeKeyListener.java: tab key behaves correctly if !editor.tabs.expand
Merge pull request #2659 from JakubValtar/svg-arc

Implemented elliptical arcs for PShapeSVG
todos and notes for the revisions
Merge pull request #2657 from joelmoniz/fixReferenceNotShowing

Help>References and Help>Environment open in default browser in Windows