Merge branch 'master' of github.com:bedatadriven/renjin into wip-optimize

Conflicts:
	packages/stats/src/main/java/org/renjin/stats/dist/DistanceMatrix.java
	packages/stats/src/main/java/org/renjin/stats/dist/Euclidean1dDistanceTriangle.java
Merge branch 'wip-optimize' of github.com:bedatadriven/renjin into wip-optimize

Conflicts:
	packages/stats/src/main/java/org/renjin/stats/dist/Euclidean1dDistanceTriangle.java
WIP