bump version number to 0.4.9
bump version number to 0.4.9

lukas-zech-software/node-lmdb,lukas-zech-software/node-lmdb,Venemo/node-lmdb,lukas-zech-software/node-lmdb,Venemo/node-lmdb,lukas-zech-software/node-lmdb,Venemo/node-lmdb