Spec updates for method parameter reflection

[Alex Buckley]

I have updated the spec to describe the core reflection API and language 
model API for method (and constructor) parameters.

I also give a rationale for Oracle's new policy of _not_ storing 
parameter names in class files by default.

For repeating annotations, there is a clarification of the rule about 
mixing annotations of repeatable and containing annotation types on the 
same declaration (see page 8), and minor corrections to the core 
reflection API examples and the language model API description.

The spec is at http://cr.openjdk.java.net/~abuckley/8misc.pdf as usual.

Alex