o.e.email.ui: Move image snapshot and dialog in another UI Runnable

Fixes #241: On Linux, context menu which invoked the email action was
still visible and thus included in BOY screenshots
o.c.email.ui: Check for empty 'from:', 'to:' in ELog Dialog

Prevent 'OK' unless both fields contain something.
o.c.email.ui: Update version number
o.c.opibuilder, beast.ui, trends.databrowser: Clear default email

When users send screenshots or alarms via email, they now need to enter
a "from:" email address. The default values, e.g. "opi@css", didn't tell
the recipient who sent the email, making it hard to reply.

Sites who want to use default 'From:' email addresses can add this to
their site-specific plugin_customiation.ini (as before).
o.c.utility.pvmanager.widgets: Make VTable widget font update w/ zoom

When BOY display is zoomed, it updates the fonts of all widgets.
The VTable widget - a composite - didn't update the fonts of its
internal components, so overall its fonts didn't zoom
o.c.scan: Define scan_config.xml to replace beamline.xml

There's a beamline2scan_config.xsl converter, and scan tools will still
read existing beamline.xml files, but issue warnings.
Merge pull request #313 from ControlSystemStudio/bugs_email

Bugs email: Fixes #241 and #312
Merge pull request #315 from ControlSystemStudio/bug_252

o.c.utility.pvmanager.widgets: Make VTable widget font update w/ zoom: Fixes #252
Merge pull request #316 from css-iter/master

o.c.scan.ui.scantree: Icon "Open a new Scan Editor" removed
Merge remote-tracking branch 'origin/master' into bug_288
o.c.opibuilder.imagelib:[Symbol Library] Added new symbols + resized some of the existing ones
o.c.trends.databrowser2:[Data Browser] Plot XYGraph Settings are now ALL saved with the configuration file (Issue #317)
o.c.opibuilder.rap:[WebOPI] Fixed bug when startup_opi preference is set with a .plt file (Issue #318)
o.c.opibuilder.widgets.symbol:[BOY Symbols] BOY Symbol widgets now handle ForeColor Alarm Sensitive property (Issue #319)
o.c.scan: Use scan_config.xml in all tools

.. but still support beamline.xml & simulation.xml as fallback, with
warning
o.c.scan: Issue only one deprecation warning about
beamline/simulation.xml
o.c.scan: Log complete stack trace for simulation errors
o.c.scan: Simulation config didn't work with plugin:// as path
o.c.scan: Tested OK with deprecated beamline/simulation.xml
o.c.trends.databrowser2: add property "rap.hide_properties_view" to hide "properties" view on webdatabrowser perspective. ISSUE #322