CForLoop: Update internal uses of blockInfoGet/Set to cforInfoGet/Set
Replace "test" with "term" to describe the second cforLoop header clause
Cleanup CForLoop constructors
Deprecate cforInfoSet
Fix #include discrepancy between clang and gcc
Merge pull request #964 from noakesmichael/cforLoop-0

CForLoop: Begin to transition the internals away from relying on BlockStmt::blockInfo

1) Replace internal calls down to BlockStmt::blockInfoGet/Set

2) Clean up CForLoop construction

3) Deprecate cforInfoSet

Compiled: STD clang/darwin, STD gcc/linux64, LLVM gcc/linux64
Tested: paratest --verify
Review: none