adds partial function substr. the use of this function should be guarded, especially for disequalities
adds partial function substr. the use of this function should be guarded, especially for disequalities
adds some fixes. it solves kaluza problems
Merge branch 'master' of github.com:tiliang/CVC4

Conflicts:
	src/theory/strings/theory_strings.cpp
Added support for converting unsorted problems to multi-sorted problems via sort inference and monotonicity.  Minor cleanup.
Adding example proof signatures for LFSC.
Merge branch 'master' of https://github.com/CVC4/CVC4