#15 OSX Compile Problem

[pfaffian]

When compiling under OSX 10.9 with the homebrew toolset, the following errors crop up when making the build:

block_compression.c:163:5: error: non-void function 'compress_observations' should return a value [-Wreturn-type]
return;
^
block_compression.c:230:5: error: non-void function 'merge_observations' should return a value [-Wreturn-type]
return;
^
2 errors generated.
make[3]: *** [block_compression.lo] Error 1
make[2]: *** [all-recursive] Error 1
make[1]: *** [all-recursive] Error 1
make: *** [all] Error 2

Attached is a patch fixing the problems.