Changes

Update NuGet packages where available
Others require .NET 4
 (commit: b605a73)

Accessory projects on .NET 4.7.1
Visual Studio apparently requires .NET 4 to run tests now.  Main project
stays on 3.5 since KSP requires that.
 (commit: 2993250)

Update NSubstitute to latest
 (commit: 9a9bd67)

Update Xunit
 (commit: bb85860)

Fix Xunit warnings
 (commit: 0968853)

implement stream logger
log to a stream
 (commit: e03db37)

Unnecessary using
 (commit: 16d88d2)

These are already run by MMPatchLoader
No need to explicitly run them again on database reload
 (commit: 376b71f)

Extract post patch
Now its own loading system
Extract test runner and add tests for it (meta!)
 (commit: e1a2be8)

Operate on a copy of the game database then apply
* Insert nodes are now patches.  They don't support MM syntax yet (just
applied directly) but that could be added
* ProtoUrlConfig identifies a UrlFile and node without the expectation
that the UrlFile knows about the node (turned into a real UrlConfig at
the end)
* Intermedate state of the game database is now a linked list of nodes
 (commit: 48df502)

Move path initialization to static initializer
By the time the plugin is even loaded this should all exist
 (commit: 72f37f1)

Make sure cache also uses copy of game db
Configs can be applied after in either case
 (commit: 122d4bf)

Extract paths to their own class
Forgot that the static initalizers would prevent tests from running
 (commit: ea7b05a)

patch in background
Patches are now applied on a separate thread to an isolated copy of the 
game database, then copied into the actual game database by post-patch 
runner.  Post patch runner will wait for patched database if it isn't
done yet.
One consequence is that logging during patching can no longer be
directed to the main log (it'll get mixed up with other messages).  Now
directed to
<ksp_root>/Logs/ModuleManager.log
 (commit: d50fc9e)

Remove PurgeUnused
Hasn't been necessary for a while
 (commit: 09b1eff)

Put log paths in path repository
 (commit: 39e4157)

Rename file to reflect class name
 (commit: de6b621)

Dump ModuleManager log to main log after patching
Makes it easier to debug people's issues
 (commit: 6ed6702)

Don't count insert nodes as patches
As far as progress is concerned, these take much less time to apply than
patches, and are often less numerous.  This can lead to weird completion
percentages.
 (commit: 1589e07)

Only display whole percentages
 (commit: c2424cb)

Add subdir under Logs
Makes it consistent with Kopernicus
 (commit: aeca335)

Replace reloading screen messages with dialog
 (commit: ed78083)

add LogSplitter
directs logs to two other loggers
 (commit: 52d8b18)

Save patch log and dump when loading from cache
This ensures that modders have access to a full history of what
ModuleManager did even when the log was taken from a run where it loaded
from cache
 (commit: 7145003)

Get rid of stream logger's exception logger
In theory it should be monitored, and not being able to log is a pretty  
serious condition we'd want to watch for
 (commit: ee9073b)

Get rid of trailing whitespace
Thanks VisualStudio
 (commit: e0c1400)

use international date format
 (commit: 326119b)

extract common parts of reading logs from queue to its own class
 (commit: 072b0d0)

v4.0.0
 (commit: 166b72c)