create skeleton for ir_eval
add operator[] to mmap_file

replace start() with begin(), and prefer operator[] over it
clang format mmap_file
Merge branch 'mmap-operator' into develop
Merge branch 'develop' into relevance
add basic ir_eval measures
add super basic unit tests for ir_eval
add {prec,recall,f1}@k by default parameters
fix type error in debug mode
add NDCG to ir_eval
add avg precision, MAP, and gMAP
Merge branch 'relevance' into develop
increase timeouts on ranker tests
have run_test return whether test failed
update all unit tests to return whether any failed
Attempt to fix clang build in travis-ci.
Merge branch 'travis-ci' into develop
add libsvm and liblinear submodules
update libsvm-modules
support for svm_wrapper fixed