added scopes
Merge branch 'develop_2.0' of github.com:swagger-api/swagger-core into develop_2.0
renamed class to differentiate between implementation and definition
cleaned up error message, will further this soon
added file property
renamed auth definitions
renamed and added tests per #766
Java 8 compile fix

Compilation with Java 8 had failed:
reference to Parameter is ambiguous.
both class java.lang.reflect.Parameter in java.lang.reflect
and interface com.wordnik.swagger.models.parameters.Parameter in com.wordnik.swagger.models.parameters match
Failing unittests (Windows) ignored
Header, cookie, and form parameters should be optional

According to the spec
(https://github.com/wordnik/swagger-spec/blob/master/versions/2.0.md#parameterObject),
only "path" parameters are required by default, while for
all other parameter types the default value is "false".
Implemented vendor-specific fields at Operation and Parameter level
Make response headers available to the code generator
Use an own version number for this fork