[LyX/master] For python 3 require at least 3.5

[Jean-Marc Lasgouttes]

commit e485102ef23de8816bd95442dd65571e3c4c2052
Author: Jean-Marc Lasgouttes <lasgout...@lyx.org>
Date:   Fri Jun 28 00:06:28 2019 +0200

    For python 3 require at least 3.5
    
    This handles configure.ac and os::python23. What remains to be done is 
cmake.
---
 configure.ac       |    2 +-
 src/support/os.cpp |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 7bf598d..fb7efb1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -40,7 +40,7 @@ for file in config/install-sh ; do
 done
 
 # Find a suitable python interpreter
-LYX_PATH_PYTHON23([2.7.0], [3.3.0])
+LYX_PATH_PYTHON23([2.7.0], [3.5.0])
 # do the usual python setup stuff
 AM_PATH_PYTHON
 
diff --git a/src/support/os.cpp b/src/support/os.cpp
index 9840ad3..c381203 100644
--- a/src/support/os.cpp
+++ b/src/support/os.cpp
@@ -65,7 +65,7 @@ static string const python23_call(string const & binary, bool 
verbose = false)
 
        int major = convert<int>(sm.str(1));
        int minor = convert<int>(sm.str(2));
-       if((major == 2 && minor < 7) || (major == 3 && minor < 4))
+       if((major == 2 && minor < 7) || (major == 3 && minor < 5))
                return string();
 
        if (verbose)