Mark all IsFastEnough tests as performance tests

This patch marks remaining/missed tests as ones belonging to
performance tests group.

Issue: SPR-9984
Merge pull request #212 from sslavic/SPR-9984

# By Stevo Slavic
* sslavic/SPR-9984:
  Mark all IsFastEnough tests as performance tests
Merge branch 'SPR-9984' into cleanup-3.2.x

* SPR-9984:
  Mark all IsFastEnough tests as performance tests
Gradle 'api' task depends on 'jar' tasks

Update the gradle 'api' task to depend on the 'jar' task of all
subprojects. This intern ensures that the 'asmRepackJar' and
'cglibRepackJar' tasks run which is critical for JavaDoc
generation.
Support "X-Forwarded-Host" in UriComponentsBuilder

ServletUriComponentsBuilder now supports setting the host to the
value held in the X-Forwarded-Host [0] header used in reverse
proxy scenarios.

[0] http://tools.ietf.org/html/draft-ietf-appsawg-http-forwarded-10

Issue: SPR-10110
Merge branch 'cleanup-3.2.x' into 3.2.x

* cleanup-3.2.x:
  Gradle 'api' task depends on 'jar' tasks
  Mark all IsFastEnough tests as performance tests
Add support for placeholders in @RequestMapping

@RequestMapping annotations now support ${...} placeholders.

Issue: SPR-9935