Update project config files for Eclipse 3.7 and use GWT 2.3.0.

Update project config files for Eclipse 3.7 and use GWT 2.3.0.

These should really be two separate tasks but I counldn't get things to
work with GWT 2.2.0 and Eclipse 3.7.

* .classpath:
* .project:
* .settings/org.eclipse.jdt.core.prefs:
* .settings/org.eclipse.jdt.ui.prefs:
* .settings/org.eclipse.ltk.core.refactoring.prefs:
* .settings/org.eclipse.m2e.core.prefs:
Add new config files. Update current files. Remove references to the
webtools plugins as we're not using any of the webtools features.
* .gitignore: Add logs directory which is created when running with
'mvn gwt:run'.
* pom.xml: Update to GWT 2.3.0. Eclipse configuration was automatically added.
* src/main/java/org/glom/web/OnlineGlom.gwt.xml: Moved from
src/main/resources/org/glom/web/OnlineGlom.gwt.xml as per this known
limitation:
http://mojo.codehaus.org/gwt-maven-plugin/eclipse/google_plugin.html#Limitations