Emscripten 0.8!

The main highlights of this release are:

• Tests for FreeType and zlib, two important real-world codebases. Aside from all the fixes and improvements necessary to get them to work, the test infrastructure now runs the entire build procedure (using emmaken) for those two tests, giving even more complete test coverage.
• File emulation. Just enough to let compiled C/C++ code think it is accessing a filesystem. For example, the FreeType test loads a TrueType font from a file (but really it's a virtual filesystem, set up in JavaScript).
  
• Additional compilation options for overflows and signedness (CHECK_OVERFLOWS, CORRECT_OVERFLOWS, CHECK_SIGNS). These allow even more C/C++ code to be compiled and run properly, but are switchable, so code that doesn't need them can run fast.
  

I'll post a web demo soon.