python3: bump to version 3.8

This required a bit work to get working, compared to other versions. So,
some things have changed a bit more significantly.

Some highlights:
* there is no longer a pgen executable, seems this is now part of
  libpython; let's see what this means for us in the future
* blake2 hash (from OpenSSL) detection needs some fixing; will upstream
  added patch 002-fix-blake2-detection.patch
* removed all bpo patches; those should be fixed in upstream
* some needed to be manually re-applied as stuff changed:
  - 001-enable-zlib.patch  - file changed
  - 004-do-not-write-bytes-codes.patch  - file changed
  - 015-abort-on-failed-modules.patch - variable was renamed
    cross_compiling -> CROSS_COMPILING
* 017_lib2to3_fix_pyc_search.patch - the code changed, it does not seem to
     have the original problem with respect to file-extension, as there
     does not seem to be any special extension logic anymore there
* 006-remove-multi-arch-and-local-paths.patch - dropped patch; I can't
     remember the full-details of this issue; it was something with
     Debian/Ubuntu's multi-arch stuff; it was probably added maybe due to
     some overzealous (on my part) thingy caused by some weird reports,
     that I could never solve; let's have this patch dropped and see
* make package/python3/refresh to reduce fuzz for the rest

Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>

lang/python/python3/patches/014-remove-platform-so-suffix.patch

@@ -1,6 +1,6 @@
 --- a/configure
 +++ b/configure
-@@ -15273,7 +15273,7 @@ $as_echo_n "checking ABIFLAGS... " >&6;
+@@ -15142,7 +15142,7 @@ $as_echo_n "checking ABIFLAGS... " >&6;
  $as_echo "$ABIFLAGS" >&6; }
  { $as_echo "$as_me:${as_lineno-$LINENO}: checking SOABI" >&5
  $as_echo_n "checking SOABI... " >&6; }
@@ -11,7 +11,7 @@
  
 --- a/configure.ac
 +++ b/configure.ac
-@@ -4736,7 +4736,7 @@ AC_SUBST(SOABI)
+@@ -4633,7 +4633,7 @@ AC_SUBST(SOABI)
  AC_MSG_CHECKING(ABIFLAGS)
  AC_MSG_RESULT($ABIFLAGS)
  AC_MSG_CHECKING(SOABI)
@@ -19,4 +19,4 @@
 +SOABI='cpython-'`echo $VERSION | tr -d .`
  AC_MSG_RESULT($SOABI)
  
- AC_SUBST(EXT_SUFFIX)
+ # Release and debug (Py_DEBUG) ABI are compatible, but not Py_TRACE_REFS ABI