Introduce cache.memory_ratio configuration for HPCache

New set-and-forget configuration that specifies cache size as a ratio of the
old generation max size. Memory division across internal components of the cache
is handled by fixed ratios.

If any of the old config (now referred to as "advanced config") is set, it will
override the memory_ratio configuration.
Everything not starting with 'cmdchar' is cypher.

* Also remove old debug message
Change dest to 'fonts'.
Update Codemirror

* Codemirror 4.5
* angular-codemirror-ui 0.1.6
Fix Codemirror shortcuts

* Moving some keys from global listening.
* Move Codemirror keymap config to Editor class.
* Run $digest upon codemirror model update.
* Mac shortcuts fixed (Cmd-Up/Down/Enter)
Improvements to the application pause monitor.

- Use System.nanoTime() to remove false-positive from network time adjustments
  and other external factors.
- Don't track total block time, It isn't a useful metric and it was confusing.
- Have the "trigger" level be the max block time that's acceptable, rather than
  the max block time plus the monitor pause interval.
- Bump the default block time trigger level to 200ms
- Introduce a manual mechanism to verify that the monitor works.
Unpacking of transaction logs occurs right after response deserialization
Introduce an Exists predicate to be used in the absence of meaningful predicates on a node
Fix Muninn memory leak from pool PageCursors

The cursor freelists were anonymous inner classes of the MuninnPagedFile class,
and this meant that they were accidentally strongly referencing the Page
freelist.
This meant that if we made use of thread-local PageCursor pooling, the cursor
freelist would keep all pages alive that could be reached through the page
freelist. And the cursor freelists were kept alive by the cursors, who in turn
was kept alive by thread-local references.
This way, a potentially very large amount of pages could be kept live after the
page cache had been shut down, because threads that had accessed it were still
running.
This was especially a problem for unit tests, since they fork only a few JVMs,
have a main thread that runs all tests, and many tests start and stop database
instances, and thereby also starts and stops page caches.

The fix was to make the cursor freelist classes static, so they no longer hold
a reference to the page freelist. Further more, the page freelist is now also
nulled out when the cache shuts down, even though this isn't strictly
necessary for fixing this issue.
Reenable the advesarial FSA based page cache test

Muninn was already passing it and we don't have the StandardPageCache any more
Simplify the PageCursor pooling

Since we have MuninnPageCursorPools for every PagedFile, and since a thread can
only use a single cursor at a time, per PageCache, without risking deadlocks,
it makes no sense to pool more than a single cursor.

Therefore, this commit drops the freelist concept, so we just have a single
thread-local variable that points to whatever cursor instance has been created.
The PageCache now throws exceptions when used in a thread-unsafe way
Revert of "Remove non-versioned elections (2602)" pull request
Merge pull request #3097 from lutovich/aioob-exception-in-lock-requests

[master] Unpacking of transaction logs occurs right after response deserialization
Merge pull request #3116 from chrisvest/2.2-muninn-cursor-pool-leak

2.2 Fix Muninn memory leak from pool PageCursors
Proper lifecycle of dummy index extension

DummyIndexKernelExtensionFactory pretended to be many things at once, an
extension factory, and extension and an index implementation. It only
implemented one init() method, which registered the index provider, but it
got called three times, once for each "role" it had.
Counts command now always writes the command type header

and will not even exist as a command in the transaction if the delta was
0. This fixes a problem where the reader, always expecting a command type
after a command log entry header to be there, failing to read that
command.
Fixes an issue with high id being too high after recovery

due to giving the IdGenerator the wrong highId in its constructor. It used
to give it fileSize/recordSize, but now gives it the highest inUse record id.

Also deduplicated 3 versions of rebuildIdGenerator, 2 versions of
figureOutHighestIdInUse (which was badly named btw) and some other
deduplication.
Merge pull request #3095 from tinwelint/1.9-fix-too-high-id

[1.9] Fixes an issue with high id being too high after recovery
Make predicate combination easy to change, and change it to assume dependence