2.0.0-0.1.rc2 - Update for new upstream tarball
    
    ... for release candidate: Pacemaker-2.0.0-rc2,
      for full details, see included ChangeLog file or
      https://github.com/ClusterLabs/pacemaker/releases/tag/Pacemaker-2.0.0-rc2
    
    Adapt spec file more akin to upstream version including:
    . out-of-tree change from 1.1.18-2 build got subsumed (508ad52e7)
    . %%{_sysconfdir}/pacemaker path got properly owned
      (-cli package; f6e3ab98d)
    . -libs package started to properly declare Requires(pre): shadow-utils
      (293fcc1e8 + b3d49d210)
    . some build conditionals and dependencies dropped for no longer
      (snmp, esmtp; f24bdc6f2 and 1f7374884, respectively) or never
      being relevant (~bison, byacc, flex; 61aef8af4)
    . some dependencies were constrained with new or higher lower bounds:
      corosync needs to be of version 2+ unconditionally (ccd58fe29),
      ditto some others components (~GLib, 1ac2e7cbb), plus both 2 and 3
      versions of Python are now (comprehensively for the auxiliary
      functionality where used) supported upstream with the latter being
      a better fit (453355f8f)
    . package descriptions got to reflect the drop of legacy low-level
      cluster infrastructures (55ab749bf)
    
    Adapt spec file akin to current packaging guidelines including:
    . drop some redundant/futile expressions (defattr, "-n %%{name}-libs"
      instead of plain "libs", "timezone hack"), add some notes for future
    . make -cts and -doc packages noarch (former enabled with 088a5e7d4)
    . simplify "systemd_requires" macro invocation, and relax it to
      "systemd_ordering" for -remote package where possible so as not
      to drag systemd into a lightweight system setup (e.g. container)
      needlessly
    . adjust, in a compatible way, common ldconfig invocation with
      post{,un} scriptlets
      (https://fedoraproject.org/wiki/Changes/Removing_ldconfig_scriptlets)
    . drop some more unuseful conditionals (upstart_job)
    
    Apply some regression fixes on top as patches (PR #1457, #1459)
    
    Signed-off-by: Jan Pokorný <jpokorny@redhat.com>