Change autoconf version to 2.62 and automake version to 1.11.2

Change autoconf version to 2.62 and automake version to 1.11.2

On my computer, the version of autoconf is 2.59 and automake is 1.9
I build with autogen.sh & configure & make and failed.

I find In Makefile.am:
    include/event2/event-config.h: config.h make-event-config.sed
        $(AM_V_GEN)test -d include/event2 || $(MKDIR_P) include/event2
        $(AM_V_at)$(SED) -f $(srcdir)/make-event-config.sed < config.h > $@T
        $(AM_V_at)mv -f $@T $@

There are three undefined variables: MKDIR_P, AM_V_GEN and AM_V_at.
Then I tried:
- autoconf-2.60 / automake-1.10
- autoconf-2.61 / automake-1.11
- autoconf-2.62 / automake-1.11.2

And only autoconf-2.62 & automake-1.11.2 is ok.

Therefore, I recommend changing the autoconf version from 2.59 to 2.62
and automake version from 1.9 to 1.11.2.

Plus autoconf 2.59 is too old - 2003.12.16 [1], so as automake 1.9 -
2004.08.11 [2], while $(AM_V_GEN)/$(AM_V_at) had been introduced in
371a1237 back in 2012.

  [1]: http://ftp.gnu.org/gnu/autoconf/
  [1]: http://ftp.gnu.org/gnu/automake/

Fixes: 371a1237 ("Make quiet build even quieter")