HBASE-29036 Backport missing UI patches to branch-2.6

[PDavid]

Cherry-picked the following patches which were missing on branch-2.6 branch. Most of these applied as a clean cherry-pick (without conflicts). Unfortunately there were some which had conflicts and I manually resolved them.
Each commit message contains from which commit it was cherry-picked from.

• HBASE-18382 add transport type info into Thrift UI (HBASE-18382 add transport type info into Thrift UI #880)
• HBASE-20693 Refactor thrift jsp's and extract header and footer (HBASE-20693 Refactor thrift jsp's and extract header and footer #5732)
• HBASE-24624 Optimize table.jsp code (HBASE-24624 Optimize table.jsp code #1963) - ⚠️ This did not apply cleanly - had to resolve conflicts manually
• HBASE-25402 Sorting order by start key or end key is not considering empty start key/end key (HBASE-25402 HBase UI: sorting order by start key or end key is not considering empty start key/end key #2955)
• HBASE-28778 NPE may occur when opening master-status or table.jsp or procedure.jsp while Master is initializing (HBASE-28778 NPE may occur when opening master-status or table.jsp or procedure.js… #6152)