Remove free_long and free_double
Fix code style
Write compressive storage test
Increment forgetting weight all of when carry up occurrs
Set forgetting_threshold in test
Modify behavior of remove_row of lsh_index_storage before/after MIX.
Merge remote-tracking branch 'upstream/develop' into remove_free

Conflicts:
	jubatus/core/clustering/kmeans_compressor.cpp
Remove unnecessary serialize method
Refactor
Fix RPC error handling in linear_mixer
fix set_label argument name to new_label (refs #706)
Use partial_sort
Return error code with `unknown error`
Merge pull request #731 from jubatus/fix-729

Fix RPC error handling in linear_mixer: fixes #729
Fix jubatus servers to stop mixer before RPC server stopped

fixes #730
Print log when error occurred during forwarding requests
Eliminate ADL (which is evil) from test of lof_storage
Add test for issue #721
Clear model before unpacking
Add dummy clear for clustering