load current directory file

jruby 9k rc2 can't load a file in current directory.

```
$ touch test.rb

# jruby 9k rc2
$ jruby -e 'load "test.rb" ; puts "OK"'
LoadError: no such file to load -- test.rb
   load at org/jruby/RubyKernel.java:958

# jruby 9k rc1
$ jruby -e 'load "test.rb" ; puts "OK"'
OK

# MRI
$ ruby -e 'load "test.rb" ; puts "OK"'
OK
```
