fix bit_index_storage to erase rows with empty vector on MIX
fix bit_index and inverted_index erase rows locally
Remove serialization methods for clustering
Detect IO errors in save
Remove unnecessary logs
Devide open error and read/write error
Detect IO error in load
Remove incomplete file
mix number should be output as ordinal number fix #552
classifier: add `set_label` and `get_labels` for fix #655
cpplint ok
local_storage_mixture::set/get_label(s) is tested by `storage_test.cpp`
add setter/getter of cluster name, fix #668
don't mix when no update observed, fix #181
Merge pull request #707 from jubatus/feature/setter_getter_of_clustername

add setter/getter of cluster name, fix #668
set_label() should return boolean instead of integer
Merge pull request #706 from jubatus/feature/set_get_labels

setter/getter of labelset in classifier
Add warning message when failed to remove
jenerated by old generator
remove unnecessary namespace prefix