Move the `-lm` after the list of object files
Move the `-lm` after the list of object files

Fixes linking through `gcc`, doesn't affect `clang`.

Closes #43

foresterre/wren,Nave-Neel/wren,lluchs/wren,Nelarius/wren,minirop/wren,Nave-Neel/wren,bigdimboom/wren,munificent/wren,Nelarius/wren,lluchs/wren,Nelarius/wren,minirop/wren,Nelarius/wren,daimajia/wren,minirop/wren,bigdimboom/wren,munificent/wren,munificent/wren,Nelarius/wren,Nave-Neel/wren,foresterre/wren,bigdimboom/wren,munificent/wren,minirop/wren,Rohansi/wren,foresterre/wren,daimajia/wren,Nave-Neel/wren,daimajia/wren,foresterre/wren,bigdimboom/wren,lluchs/wren,munificent/wren,Rohansi/wren,Rohansi/wren,daimajia/wren,lluchs/wren,Rohansi/wren,foresterre/wren,munificent/wren,minirop/wren