Added and updated API which was changed from old TStr but still fits well with new TStr.
Added and updated API which was changed from old TStr but still fits well with new TStr.
mutable methods
Merge pull request #115 from blazf/TStr

T str
Merge branch 'TStr' of https://github.com/qminer/qminer into TStr

Conflicts:
	src/glib/base/dt.cpp
	src/glib/base/dt.h