npm dedupe crashing

[springmeyer]

Looks like npm dedupe with node v4.5.0 is crashing with OOM. Not our problem, but a blocker for getting test runs to be clean.

<--- Last few GCs --->
 1391619 ms: Scavenge 1388.2 (1457.9) -> 1388.2 (1457.9) MB, 8.7 / 0 ms (+ 0.8 ms in 1 steps since last GC) [allocation failure] [incremental marking delaying mark-sweep].
 1393067 ms: Mark-sweep 1388.2 (1457.9) -> 1383.1 (1457.9) MB, 1447.8 / 0 ms (+ 11.2 ms in 104 steps since start of marking, biggest step 1.2 ms) [last resort gc].
 1394468 ms: Mark-sweep 1383.1 (1457.9) -> 1386.1 (1457.9) MB, 1401.0 / 0 ms [last resort gc].
<--- JS stacktrace --->
==== JS stack trace =========================================
Security context: 0x32169cb4629 <JS Object>
    1: _readdirEntries [/home/travis/.nvm/versions/node/v4.5.0/lib/node_modules/npm/node_modules/read-package-json/node_modules/glob/glob.js:~544] [pc=0x2ec6c43d9023] (this=0xb946f372bb9 <a Glob with map 0x3bc121df6a49>,abs=0xb946f372a61 <String[158]: /home/travis/build/mapbox/mapnik-swoop/node_modules/geojson-mapnikify/node_modules/coveralls/node_modules/request/node_modules/bl/node_modules/rea...
FATAL ERROR: CALL_AND_RETRY_LAST Allocation failed - process out of memory
/home/travis/build.sh: line 45:  3766 Aborted                 (core dumped) npm dedupe