Revert "Reduced memory consumption at server start by removing an apparently unnecessary meta-data copy operation..."

This reverts commit 3a5822aaf119dc2bbeb2e5e15d742205034d3116.
Added two new items to the glossary.
Made copy edit.
Made copy edit.
Made another copy edit.
Merge pull request #972 from zhouyaoji/docs_glossary_update

[doc] Added a couple of glossary items.
Merge pull request #969 from drewfish/revert-3a5822a

Revert commit 3a5822a
lock yahoo-arrow version to 0.0.73
Merge pull request #974 from drewfish/arrow73

lock yahoo-arrow version to 0.0.73