Extend database format to handle statements and methods in a file

Allow better modelling of file-level statements and methods so that we can better support languages like Ruby which support top-level scripting constructs.

Example:

session.enterFile(..);
session.enterMethod(...); // top-level-method, not inside a class
...
// some statements
...
session.exitMethod();
...
session.addStatement(...); // top-level-statement, not inside a class or a method
...
session.exitFile();

Some preparation have been already done for Java 8 (Clover 3.2).

Things to be checked:

• how our code calculates the start/end line/col range for a statement/method outside a class
• how it calculates code metrics for a file having top-level statements/methods
• how it handles exclusion filters (statement/method regexp)
• how it handles nested entities (method-in-method etc)

Things to be implemented:

• take into account these top-level statements/methods in reporting
  • show in XML / HTML / PDF / JSON
  • render lines
  • show in tables etc

Out of scope:

• test optimization

Note:
Looking at how Clojure is written, for any Clojure file there would only ever be one FileInfo containing lots of StatementInfos and MethodInfos but no ClassInfos.