[BW]: [Fix] Fixed CMakeLists.txt configuration related to reading/setting INVICTUS_ROOT environment variable. Previously committed code conyained improper syntax (missing $ at ENV call)
[BW]: [Ign] BOOST_ROOT variable inside setenv.bat should be redefined only if it doesn't not exist.
[BW]: [Ign] gMiningIsPossible variable initially set to true since it determines only some GUI part visibility.