Fix a bug in the *.spec files and also apply the following major changes:

- Add support for adding the base folder to PATH.
- Only display one pop up window at a time in order to avoid confusion.
- Add automatic updates feature:
	- Windows and Linux versions will be shipped with an updater program used to
	  update both Artemis and the updater itself.
	- MacOs versions will not have the updater. Instead the user will be asked
	  to download the new software version (if present) via browser.

src/os_utilities.py

@@ -0,0 +1,34 @@
+import sys
+from constants import SupportedOs
+
+
+def _is_mac_os():
+    """Return True if running OS is Mac."""
+    return sys.platform == 'darwin'
+
+
+def _is_win_os():
+    """Return True if running OS is Windows."""
+    return sys.platform == 'win32'
+
+
+def _is_linux_os():
+    """Return True if running OS is Linux."""
+    return sys.platform == 'linux'
+
+
+IS_MAC = _is_mac_os()
+IS_LINUX = _is_linux_os()
+IS_WINDOWS = _is_win_os()
+
+
+def get_os():
+    """Get the name of the current running operating system."""
+    if IS_WINDOWS:
+        return SupportedOs.WINDOWS
+    elif IS_LINUX:
+        return SupportedOs.LINUX
+    elif IS_MAC:
+        return SupportedOs.MAC
+    else:
+        raise Exception("ERROR: OS not recognized.")