Allow making Jetty the default server via configuration.

We are using the standalone plugin as a dependency for another build related
plugin which packages the grails application as an RPM.  My plugin calls
buildStandalone() within it's own GANT task.  Since the standalone plugin
relies completely on command line arguments to change the server, it makes using
Jetty instead of Tomcat very difficult in this manner.

By adding the configuration option, we gain the necessary flexibility without
losing any current functionality.  A user can now use the following config
option to make Jetty the default:

grails.plugins.standalone.useJetty = true

A complementary flag is being added as well, which will allow you to override
the Jetty default in the same manner you would override the Tomcat default:

grails build-standalone --tomcat
Merge pull request #3 from ajbrown/master

Add useJetty configuration option to change default server.
copyright update
updated release plugin
added non-exported Jetty dependencies so the runtime source can be a source folder in GGTS
changed from ordered commandline args to named args using foo=bar syntax, and added support for truststore path and password, compression, enabling client auth, session timeout, and specifying workDir and whether to use NIO from the commandline
made nearly everything configurable and moved settings to BuildConfig
cleanup
added release script
doc update
using the proper property naming convention, and changed to be in BuildConfig instead of Config
1.2 release
Merge branch 'master' into gh-pages
1.2 release