Replace internal uses of blockInfoGet/Set with condExprGet/Set in WhileStmt*
Remove specialized versions of :verify from WhileDo/DoWhile
Update the WhileStmt* constructors to accept the condExpr as well as the body
Introduce mCondExpr, currently a CallExpr, and the associated replaceChild method
Inline the trivial uses of WhileStmt::condExprSet()
Fix syntax error for LLVM
Merge pull request #937 from noakesmichael/whileStmt-0

1) Convert internal uses of blockInfoGet/Set for WhileStmt* to condExprGet and inline uses of condExprSet

2) Introduce WhileStmt::mCondExpr to replace reliance on BlockStmt::blockInfo


Compiled: STD clang/darwin, STD gcc/linux64, LLVM gcc/linux64
Tested: paratest --verify
Review: None