#1: Solution template support
2 things for customizations: imports and helper code (inside solution class).
Options are at application level (per IDEA installation)
+ SolutionCfg model for holding configuration
+ ConfigurationService for storing SolutionCfg in .IdeaIC13/config/options/IntelliJCoder.xml
+ ConfigurationForm for editing SolutionCfg in IDEA Setting window.