hblog: cli arg modes override each other + tier2glob_map extended
hblog: cli arg modes override each other + tier2glob_map extended

Summary: Usability,
instead of giving confusing error messages, just
set the mode that was mentioned last.

Configuration,
tier2glob_map config data structure, now supports
tiers that have a common prefix and tiers that have
a common ending.

Test Plan:

  hblog --detail --follow --summary

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