Allow click option on link to take a proc
in_bounds? for TextBlock

TextBlock's claim to be clickable, but weren't doing correct bounds
checking.

This commit implements the bounds checking in the backend class and
delegates to it from the DSL.
Fix for hang during painting

We had an odd problem where opening an alert dialog right after adding
an element would cause hangs in the app. This was a result of the
element not having been placed yet, and the painter for it crashing in a
spot that SWT wasn't good about reporting the error back.

This commit now provides a check for the object to make sure that it's
positioned, and also has a rescue clause to keep errors from escaping.
Force positioning before allowing dialogs

This allows the common painters to get the positioning they need before
SWT's open triggers paint events on unpositioned elements.
Fix for flipped logic on positioned? in painter

Also consolidated to use just absolute_left/top and added a spec.
Fix spec failure for line

Changes in requirements for painter to run weren't set properly in this spec.
update .ruby-version to 1.7.12
Merge pull request #661 from shoes/click_proc

Allow click option on link to take a proc
Some specs for the painter and the positioned functionality
Merge branch 'master' into painter_alert_fail
Log an error message for swallowed errors + fix shape

* definitely logging and maybe something better otherwise way too
  many errors may escape us.. or evaluate if we really need that
  swallow everything rescure clause
* keeping shape up with dimensions... really need to get it
  dimensionized :(
expert-definr is not working anymore see #663
Add TextBlock#contents

The proper values for this were already being saved on the TextBlock
class, so we just needed an accessor.

Resolves #163.
Removing unnecessary app.gui.flush calls from manual
Merge pull request #665 from shoes/implement_contents

Add TextBlock#contents
Merge pull request #666 from shoes/remove_manual_flush

Removing unnecessary app.gui.flush calls from manual
Safer in_bounds? check

Original version of the bounds checking was, for whatever strange reason
made sense to me at the time, modifying the bounds we got back to do a
contains? check. This is odd and potentially hazardous (if layouts
didn't return a clean copy of bounds).

Additionally in reviewing it, I realized the logic fit much more cleanly
within the FittedTextLayout class itself, so I moved it along with
removing the strangeness.
Merge pull request #662 from shoes/para_clicking

in_bounds? for TextBlock
Fixes for text cursor specs

When we changed from having the app instead of the DSL create things (or
one of those moves) it broke these tests. They're now lined back up with
how things actually work on the cursor creation.