Travis: compile the interfaces only with clang
Travis: matrix exclusion only works with exact match
minor edits in eigen3
Merge pull request #983 from lambday/develop

Few edits in regarding EigenSparseUtil class in eigen3.h and eigen3.cpp
drop flaky subgradientsvm / lpm
don't fail on b0rken R modular tests / examples
require ruby 1.9.1 on travis
drop subgradient svm/lpm from ui
Fix SubgradSVM and SubgradLPM removal in SGInterface
Travis: remove commas from package list for ruby
Fix ruby call in test_ruby_narray in configure script
Try fixing ruby-narray error by enforcing to use ruby1.8