Add update option.

If rsstube was cloned with git, use -U flag to pull updates.

README.md

@@ -16,6 +16,11 @@ rsstube is written in Python, an interpreted language. There's no need to compil
 - python3
 - python3-pycurl
 
+### Optional Dependencies
+
+- git (for updating via git)
+- python3-GitPython (for updating via git)
+
 ### Sample Installation
 
 `git clone https://negativezero.link/code/0x80/rsstube.git`
@@ -24,7 +29,9 @@ rsstube is written in Python, an interpreted language. There's no need to compil
 
 ### Updating
 
-If you installed with git, just `cd` into the directory and `git pull`.
+If you installed rsstube with git, and you have python3-GitPython installed, use `rsstube -U` or `rsstube --update`.
+
+If you installed rsstube another way (manual download, package manager), update rsstube that same way.
 
 
 ## Usage

scripts/options.py

@@ -20,16 +20,31 @@ You should have received a copy of the GNU General Public License
 along with this program.  If not, see <https://www.gnu.org/licenses/>.
 """
 
-def options(params):
-	import sys,getopt,glob
-	from utils import debug,notify,warn,error
-
 # get installation path
 import os.path
 path = os.path.realpath(os.path.abspath(__file__))
 path = path[0:path.rfind("/")]
 path = path[0:path.rfind("/")]
 
+def update():
+	if os.path.isdir(path + "/.git"):
+		print("rsstube appears to have been downloaded with git.")
+		try:
+			import git
+			print("Attempting to update rsstube...")
+			g = git.cmd.Git(path)
+			output = g.pull()
+			print(output)
+		except ImportError:
+			print("python3-GitPython must be installed to update rsstube this way.")
+			print("If you don't want to install python3-GitPython, you can run `git pull` in the directory where rsstube was installed.")
+	else:
+		print("rsstube appears to have been manually downloaded or installed with a package manager. Use that same method to update.")
+
+def options(params):
+	import sys,getopt,glob
+	from utils import debug,notify,warn,error
+
 	# general settings
 	network = True
 
@@ -115,6 +130,9 @@ def options(params):
 			d["tls_max"] = arg
 		elif opt == "--tls13-ciphers":
 			d["tls13_ciphers"] = arg
+		elif opt in ("-U", "--update"):
+			update()
+			sys.exit()
 		elif opt in ("-v", "--verbose"):
 			verbosity = 4
 		elif opt == "--verbosity":