Don't allow generated strings (key names) to be empty
Merge pull request #1353 from dansanduleac/bugfix/failing-derived-settings-tests

SettingsTest: Don't allow generated strings (key names) to be empty
Roll back Ivy to 2.3.0 for 0.13.5
Remove stale, commented out code from Incremental.scala

The commented out code was sitting here since 2010. It bit-rotted to the
point of not being useful anymore. Let's remove it.
Fix resolving Select(ThisProject)
Add scripted test to verify ThisProject is resolved properly
JDK8 compat issue, MaxPermSize removed since JDK 8
Merge pull request #1357 from sbt/wip/roll-back-ivy

Roll back Ivy to 2.3.0 for 0.13.5 for #1356
Break Incremental.scala into smaller files.

Incremental.scala contained all three strategies of incremental
compilation:

  * ant-style
  * the default one (before name hashing)
  * name hashing

Let's move all those classes into separate files. Also, move common code
into a separate file.
Merge pull request #1360 from gkossakowski/incremental-cleanup

Incremental cleanup
Changed to combine SuiteResult with same name, instead of replacing with latest one. This solves the test result count problem when a Suite is executed more than 1 time due to being returned as nested suites (sub-task).
Merge pull request #1364 from scalatest/test-result-acc-count

Accumulate Test Count
0.13.5 release.
Fix import issues to generate sxr/scaladoc.
Merge remote-tracking branch 'origin/0.13.5' into wip/fix-doc-generation

Conflicts:
	project/Sbt.scala
Fix formatting issues and bump to sbt 0.13.5
Merge pull request #1359 from ancientrock/jdk8-tip

JDK8 compat issue, MaxPermSize removed since JDK 8
Merge pull request #1358 from dansanduleac/issue/1194

Resolve ThisProject properly
Revert "Load global plugins in their own class loader and replace the base loader with that.  Fixes #272."

This reverts commit 8cb7e230110e846b577539e61757e815f083294e.

Conflicts:
	main/src/main/scala/sbt/Load.scala
Re-add scripted test