Merging Branches into 3.15

Merge order already used once by ANJ:

• lp:~anj/epics-base/reorg-src
  This is a modified and possibly re-based version of lp:~mdavidsaver/epics-base/reorg-src
• lp:~anj/epics-base/epicsEvent-api
• lp:~anj/epics-base/process-get
• lp:~ralph-lange/epics-base/server-side-plugins
  I started to re-base this branch onto a test merge of the above branches, but I broke the tests in db/test in one of the re-base commits, so I didn't complete this merge and I need to start the re-base again (which is unfortunately not simple since there are conflicts with the variable-length-array-subscriptions code, amongst others).

Other branches to merge (may need reviewing first):

• lp:~dirk.zimoch/epics-base/non-val-attributes
• lp:~dirk.zimoch/epics-base/named-soft-events
• lp:~johill-lanl/epics-base/R3.15-buildCompilerSpecific when complete.
• Atomic operations branch after agreement