cli-parser (#4)

Goal of this PR should be to integrate a working CLI parser so that commands can be sent to the Printer class to print text, such as
ptprnt -t=FooBar
also, standard flags for setting the output verbosity and help should be implemented

Reviewed-on: #4

src/constants.hpp

@@ -0,0 +1,26 @@
+/* 
+    ptrnt - print labels on linux
+    Copyright (C) 2023  Moritz Martinius
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+ */
+
+#pragma once
+
+namespace ptprnt {
+constexpr const char* const APP_NAME = "ptprnt";
+constexpr const char* const APP_DESC =
+    "ptprnt - a userspace driver for Brother P-touch label printer";
+}  // namespace ptprnt