fixes for 'make dist' and 'make distcheck'

BUILD/compile-dist:
  fixes for 'make dist' and 'make distcheck'
  include yassl in "dist"
Makefile.am:
  fixes for 'make dist' and 'make distcheck'
  remove double-listing of everything in SUBDIRS and DIST_SUBDIRS
  remove @yassl_dir@, it belongs to extra/Makefile.am
  specify --basedir for mysql_install_db, in case builddir (where mysql_install_db is)
  differs from srcdir (where mysql_fix_privilege_tables.sql is)
config/ac-macros/yassl.m4:
  fixes for 'make dist' and 'make distcheck'
  create Makefile's only if yassl is used
  yassl_dir must not include /
config/ac-macros/zlib.m4:
  fixes for 'make dist' and 'make distcheck'
  create Makefile only if zlib is used
configure.in:
  fixes for 'make dist' and 'make distcheck'
  create Makefile only if a feature is enabled
  storage engine dirs must not include /
  automatically disable readline/libedit/sql-bench if source dir is missing
extra/Makefile.am:
  fixes for 'make dist' and 'make distcheck'
  remove SUBDIR/DIST_SUBDIR hack
libmysql_r/Makefile.am:
  fixes for 'make dist' and 'make distcheck'
  when symlinking all files from libmysql/ take into account that
  srcdir != builddir
libmysqld/Makefile.am:
  fixes for 'make dist' and 'make distcheck'
  remove fragile promiscuous search for object files
  if .o file is not where we look for it - extract it from the library
mysql-test/ndb/Makefile.am:
  fixes for 'make dist' and 'make distcheck'
  ndbcluster script is not a "source"
  don't forget to cleanup
plugin/Makefile.am:
  fixes for 'make dist' and 'make distcheck'
  include plugin/fulltext/configure.in template in the distribution
storage/Makefile.am:
  fixes for 'make dist' and 'make distcheck'
  remove SUBDIRS/DIST_SUBDIRS hack
storage/ndb/Makefile.am:
  fixes for 'make dist' and 'make distcheck'
  force common.mk.am out of DIST_COMMON (which is otherwise an
  auto-generated list of Makefile's sources) because it's listed
  indirectly in EXTRA_DIST, and with bk -r get, a file cannot be copied
  twice.

storage/ndb/Makefile.am

@@ -1,6 +1,7 @@
 SUBDIRS = src tools . include @ndb_opt_subdirs@
 DIST_SUBDIRS = src tools include test docs
 EXTRA_DIST = config ndbapi-examples
+DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in
 
 include $(top_srcdir)/storage/ndb/config/common.mk.am