handle exception determining whether to apply overlay
New youtube channel video extractor for https://webarchive.jira.com/browse/ARI-3865
make addRelativeToBase() and addRelativeToVia() return the link added, or null; copy getAnnotations() from CrawlURI
for ARI-3712, add extracted links relative to both via and base, and annotate with "extractorSWFRelToVia", "extractorSWFRelToBase", or "extractorSWFRelToBoth" if resulting link is the same whether relative to base or via
Unit test and other changes.
New Unit tests added now.
Merge pull request #69 from vonrosen/ari-3853

For https://webarchive.jira.com/browse/ARI-3865
Merge pull request #70 from nlevitt/ari-3712

for ARI-3712, add extracted links relative to both via and base, and annotate with "extractorSWFRelToVia", "extractorSWFRelToBase", or "extractorSWFRelToBoth" if resulting link is the same whether relative to base or via
avoid calling CheckpointService.hasAvailableCheckpoints() when crawl not launchable and therefore the info is not needed, because it calls isRunning() which is synchronized and blocks when checkpoint is in progress
Merge pull request #71 from nlevitt/checkpoint-no-ui-hang

avoid calling CheckpointService.hasAvailableCheckpoints() when crawl not...
add A_ANNOTATIONS to persistentKeys so that CrawlURI doesn't lose its annotations when deferred
Merge pull request #72 from nlevitt/persist-annotations

add A_ANNOTATIONS to persistentKeys so that CrawlURI doesn't lose its an...
Merge pull request #68 from nlevitt/handle-apply-overlay-exc

handle exception determining whether to apply overlay
Fix for HER-2068
Merge pull request #73 from kris-sigur/HER-2068

Treat codebase as link hops, not embeds