Added nonfree headers that are required for using SURF features
cmake: fixed incorrect usage of add_definitions() on Linux
cmake: PCH: use DEFINE_SYMBOL target property
Resolved the bug that the work group size is not valid.
Merge pull request #1499 from georgebrindeiro:patch-2
Merge pull request #1502 from melody-rain:2.4_Stereo_Match_Const_Space_BP
Merge pull request #1500 from alalek:fix_add_definitions