Bump the required automake version to 1.14
After the build system refactoring, we no longer call AM_PROG_CC_C_O
because it is obsolescent macro. According to the automake manual the
AC_PROG_CC
has been rewritten in automake 1.14 to not required the
call, thus we need to require at least automake version 1.14.
Closes #3151 (closed)