%extend for nested unnamed C structs
test added for nested unnamed C struct %extend
global unnamed structures ignored
obscure case workaround in std::set wrapper, where ignored type still need to be processed
Merge branch 'wkalinin-csymbols-1'

* wkalinin-csymbols-1:
  obscure case workaround in std::set wrapper, where ignored type still need to be processed
  global unnamed structures ignored
  test added for nested unnamed C struct %extend
  %extend for nested unnamed C structs
Create separate extetnd.c file for handling extensions / %extend

This is just a simple code refactor, moving and function renaming to
remove the %extend code out of the parser into its own file now
 that it isn't just used in the parser.
Add missing entries into changes files.
Python 3 byte string output: use errors="surrogateescape"

... if available on the version of Python that's in use. This allows
obtaining the original byte string (and potentially trying a fallback
encoding) if the bytes can't be decoded as UTF-8.

Previously, a UnicodeDecodeError would be raised with no way to treat
the data as bytes or try another codec.
Add "unicode_strings" test case for new Python 3 behavior
Add Python 3 'surrogateescape' documentation
Work towards C90 compatibility for Lua
Fix comment typo
Correct CFLAGS CXXFLAGS for Javascript and guile examples
Fix compiler warnings in examples when using -std=c++98 -std=gnu89 -pedantic -Wreturn-type
Fix compiler warnings in generated code when using -std=c++98 -std=gnu89 -pedantic -Wreturn-type
Javascript warnings for c++98 - remove vla
Refactor Lua class base search to make ISO c/c++ compliant
Warning fixes in test-suite
Travis testing - examples use stricter CFLAGS and CXXFLAGS
Merge branch 'stricter-examples-compilation'

* stricter-examples-compilation:
  Travis testing - examples use stricter CFLAGS and CXXFLAGS
  Warning fixes in test-suite
  Refactor Lua class base search to make ISO c/c++ compliant
  Javascript warnings for c++98 - remove vla
  Fix compiler warnings in generated code when using -std=c++98 -std=gnu89 -pedantic -Wreturn-type
  Fix compiler warnings in examples when using -std=c++98 -std=gnu89 -pedantic -Wreturn-type
  Correct CFLAGS CXXFLAGS for Javascript and guile examples