Update package.json to latest stable dependencies

Actual stable versions
"commander" 2.2.0
"mocha" 1.18.2

The tests are all fine

  lzma file decode
    ✓ should correctly decode sample0 
    ✓ should correctly decode sample1 (117ms)
    ✓ should correctly decode sample2 (217ms)
    ✓ should correctly decode sample3 
    ✓ should correctly decode sample4 (937ms)

  lzma file encode->decode
    ✓ encoded sample0 should correctly decode (648ms)
    ✓ encoded sample1 should correctly decode (2195ms)
    ✓ encoded sample2 should correctly decode (3769ms)
    ✓ encoded sample3 should correctly decode (883ms)
    ✓ encoded sample4 should correctly decode (14460ms)

  lzma streaming decode
    ✓ should correctly decode sample0 
    ✓ should correctly decode sample1 (329ms)
    ✓ should correctly decode sample2 (679ms)
    ✓ should correctly decode sample3 (271ms)
    ✓ should correctly decode sample4 (3200ms)

  range coder
    ✓ encodeDirectBits->decodeDirectBits should be the identity 
    ✓ encode->decodeBit (single context) 
    ✓ encode->decodeBit (1-bit context) 
    ✓ encode->decodeBit (2-bit context) 
    ✓ encode->decodeBit (3-bit context) 
    ✓ encode->decodeBit (4-bit context) 
    ✓ encode->decodeBit (5-bit context) 
    ✓ encode->decodeBit (6-bit context) 
    ✓ encode->decodeBit (7-bit context) 
    ✓ encode->decodeBit (8-bit context) 
    ✓ encode->decodeBit (9-bit context) 
    ✓ encode->decodeBit (10-bit context) 
    ✓ encode->decodeBit (11-bit context) 
    ✓ encode->decodeBit (12-bit context) 
    ✓ encode->decodeBit (13-bit context) 
    ✓ encode->decodeBit (14-bit context) 
    ✓ encode->decodeBit (15-bit context) 
    ✓ encode->decodeBit (16-bit context) 
    ✓ encode->decodeBit (bit-position-based context) 

  range encoder
    ✓ should pass a simple test 

  small sequence
    ✓ should pass bit tree 
    ✓ should pass bin tree (216ms)

  large sequence
    ✓ should pass bit tree (71ms)
    ✓ should pass bin tree (195ms)

  encode
    ✓ should pass its tests 


  40 passing (28s)