Fix strings containing deprecated illegal escape sequences (#648)

Python 3.6 and above has deprecated illegal string escape sequences. Escape sequences are preceded by a '\' and valid ones are "\n\t\r" etc. Illegal ones are not in the list https://docs.python.org/3/reference/lexical_analysis.html#string-and-bytes-literals.

Previous to Python 3.6 these illegal sequences were ignored and the '\' was left in place. Pylint has been noting these for a while now.

This PR corrects these sequences in Gramps. I used

find . -name "*.py" | xargs -t -n 1 python3 -Wd -m py_compile 2>&1 | grep Depre

to locate the failing strings.

windows/nonAIO/builder/build_GrampsWin32.py

@@ -222,7 +222,7 @@ class buildbase(GObject.GObject):
             os.makedirs(mo_dir)
         #TODO: find a better way to handle  different platforms
         if sys.platform == 'win32':
-            po_files = glob.glob(po_dir + "\*.po")
+            po_files = glob.glob(po_dir + r"\*.po")
             # no longer using python msgfmt as it doesn't handle plurals (april 2010)
             # msgfmtCmd = path.normpath(path.join(sys.prefix, "Tools/i18n/msgfmt.py") )
 

windows/nonAIO/builder/check_gtk_install.py

@@ -138,7 +138,8 @@ def ScanDependencyFileForErrors(fname):
             parts = line[pthend_idx:].split()
             OK = False
             if dirname.startswith(os.path.join(sysroot, 'winsxs').lower()) \
-            or dirname.startswith(os.path.join(sys.prefix, 'lib\site-packages\gtk-2.0').lower()):
+                or dirname.startswith(os.path.join(
+                    sys.prefix, r'lib\site-packages\gtk-2.0').lower()):
                 OK = True
 
             for pth in acceptablePaths:

windows/nonAIO/builder/make_launcher.py

@@ -139,7 +139,7 @@ def writeLauncher(language, langcode, runtimepath, grampspath):
 @rem During the boot process of GRAMPS there is a check for an environment variable
 @rem called GRAMPSHOME. Without this environment variable GRAMPS uses the default
 @rem windows path as the location to save all configuration files:
-@rem <system drive>\<userpath>\<application data>\gramps
+@rem <system drive>\\<userpath>\\<application data>\\gramps
 @rem If required, uncomment GRAMPSHOME line and edit to suit your use.
  ''')
     lines.append('\n@rem set the path for GRAMPS configuration files')

windows/nonAIO/check_gtk_install.py

@@ -133,7 +133,8 @@ def ScanDependencyFileForErrors(fname):
             parts = line[pthend_idx:].split()
             OK = False
             if dirname.startswith(os.path.join(sysroot, 'winsxs').lower()) \
-            or dirname.startswith(os.path.join(sys.prefix, 'lib\site-packages\gtk-2.0').lower()):
+                or dirname.startswith(os.path.join(
+                    sys.prefix, r'lib\site-packages\gtk-2.0').lower()):
                 OK = True
 
             for pth in acceptablePaths: