Use "npm install --nodedir=/usr" in charm build (#432)
Use "npm install --nodedir=/usr" in charm build (#432)

Our dependencies now include sqlite3, which needs to build a dependency
using node-gyp.  By default this will try to fetch a header bundle from
nodejs.org, which isn't permitted in JenkaaS.  Tell it that it can use
the perfectly good headers in /usr instead.
canonical-ols/build.snapcraft.io,canonical-websites/build.snapcraft.io,canonical-ols/build.snapcraft.io,canonical-websites/build.snapcraft.io,canonical-ols/build.snapcraft.io,canonical-websites/build.snapcraft.io