Add logging OS version. Deprioritize some messages to debug, so devs can run at info level with less spam (and much less impact on recalc times).

pyfa.py

@@ -18,6 +18,7 @@
 # along with pyfa.  If not, see <http://www.gnu.org/licenses/>.
 # ==============================================================================
 
+import platform
 import os
 import re
 import sys
@@ -242,6 +243,8 @@ if __name__ == "__main__":
         except ValueError, Exception:
             pyfalog.critical("Cannot redirect.  Continuing without writing stderr to log.")
 
+        pyfalog.info("OS version: {0}", platform.platform())
+
         pyfalog.info("Python version: {0}", sys.version)
         if sys.version_info < (2, 7) or sys.version_info > (3, 0):
             exit_message = "Pyfa requires python 2.x branch ( >= 2.7 ).\nExiting."