…nt level (#933)

* jruby-1_7:
  spec how non-public inner classes currently behave on the Ruby constant level (#933)
  delegate java_send with 1-3 args.length to overloaded versions - less array mangling
  [find-bugs] do no ask for getMethodsForWrite() twice esp. since its synchronized
  [find-bugs] avoid potentially creating the same File instance twice
  [find-bugs] avoid unnecessary calling getRuntime() and getCurrentContext() twice
  [find-bugs] use local map instead of calling the same method again in ScriptingContainer
  [find-bugs] avoid calling same method twice - keep module.getClass(Type) locally
  [find-bugs] avoid string concatenation while using a StringBuilder + guess size
  [find-bugs] avoid using a ternary operator to cast a boolean to true/false
  [find-bugs] inefficient string buffering - avoid passing concatenating string to builder
  [find-bugs] inner private classes can be made static
  [find-bugs] equalsIgnoreCase with "" (empty string) passed
  [find-bugs] avoid some String instances of length == 1 in favor of chars
  [find-bugs] use System.arraycopy instead of manual array-copy (of stack-traces)
  [find-bugs] (private) inner classes that can be mate static
  Fix java_implements for multiple interfaces
  Remove redundant test-jruby-jars (complete tests same stuff).
  Fix jruby versions in antlib/extra.xml.
  [build] use yecht-1.1-SNAPSHOT
  Update to jnr-ffi-2.0.4-SNAPSHOT for #3258.

Conflicts:
	.travis.yml
	antlib/extra.xml
	core/pom.xml
	core/src/main/java/org/jruby/Ruby.java
	core/src/main/java/org/jruby/RubyClassPathVariable.java
	core/src/main/java/org/jruby/RubyDir.java
	core/src/main/java/org/jruby/RubyModule.java
	core/src/main/java/org/jruby/RubyProc.java
	core/src/main/java/org/jruby/java/proxies/JavaProxy.java
	core/src/main/java/org/jruby/javasupport/JavaSupport.java
	core/src/main/java/org/jruby/runtime/ThreadContext.java
	lib/ruby/shared/jruby/compiler/java_class.rb
	spec/java_integration/jrubyc/java/implements_spec.rb
	spec/java_integration/types/retrieval_spec.rb