title: installing VIM8.1 on CENTOS7 for user with support to python3.7 fails
body: <p>I am trying install vim8.1 as a local user on CENTOS7, following the procedure found <a href="https://github.com/Valloric/YouCompleteMe/wiki/Building-Vim-from-source" rel="nofollow noreferrer">https://github.com/Valloric/YouCompleteMe/wiki/Building-Vim-from-source</a> [here], but with some changes.</p>
  
  <p>I get into problem with the python 
  fatal error: <code>Python.h: No such file or directory
   #include &lt;Python.h&gt;</code></p>
  
  <p>After cloning vim I do the following, without error:</p>
  
  <p><code>./configure --with-features=huge --enable-multibyte --enable-rubyinterp=yes --enable-python3interp=yes --with-python3-config-dir=/usr/local/lib/python3.7/config-3.7m-x86_64-linux-gnu --enable-perlinterp=yes --enable-luainterp=yes --enable-gui=gtk2 --enable-cscope --prefix=/home/myuser</code></p>
  
  <p>I am setting python3.7 (which is the python version I am using) as "pypython3-config-dir", but it seems to find python3.4:</p>
  
  <p><code>cc -std=gnu99 -c -I. -I/home/myuser/env/env3/include/python3.4m -pthread -fPIE  -Iproto -DHAVE_CONFIG_H     -g -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1        -o objects/if_python3.o if_python3.c</code></p>
  
  <p>This is strange to me, but more problematic is that it cannot find the Python.h. This happens also when I add <code>/usr/include/python3.4m</code> when the file Python.h is located to the PATH:</p>
  
  <p><code>PATH=/usr/include/python3.4m:$PATH</code></p>
  
  <p><code>echo $PATH</code> shows that it is there.</p>
  
  <p>Can anyone help me with this? I imagine that keeping version 3.4 in the installation of vim is not a problem for me.</p>