Fix for github issue #59, segmentation fault after failure to load external schema
Merge pull request #60 from cjheath/master

Fix for Github issue #59, segmentation fault after failing to load external schema
Fix potential segfault when GC occurs while creating ns from xpath

rxml_xpath_object_wrap() was creating a Ruby array and it looks like
Ruby's garbage collection was unable to find it on the stack.
Merge pull request #61 from ender672/xpath_namespace_gc

Fix potential segfault when GC occurs while creating ns from xpath
To fix XML::Writer.set_quote_char UT, wrong expected string (#63)
Merge pull request #64 from julp/fix_writer_quote_char_ut

To fix XML::Writer.set_quote_char UT, wrong expected string (#63)