HER-2039: Initial work. Eliminated Link class and dealt with resultant
errors. Not tested any further than that.
Basic revisit notation framework
Simplified revisit writing. Uses revisit profile attached to CrawlURI.
Ensure CrawlURI discards RevisitProfile after it has finished, in case
the same CrawlURI is issued again.
IdenticalDigestDecideRule now consults the new revisit profile mechanism
on the CrawlURI to determine if it represents an identical digest
revisit.
Corrected javadoc
Profiles refactored, shared elements in AbstractProfile.
WARC-Refers-To-Date now set as long and correctly formated in
getWarcHeaders.
Revisit profile is now populated with original URI and date.
Store refersToDate in String format (as intended to write in WARC).
Retain long setter for convenience.
Revisit headers now come correctly formated from the revisit profile.
ContentDigestHistoryLoader now sets the revisit profile on the CrawlURI
after determining that it is a revisit.
Merge remote-tracking branch 'internetarchive/master' into revisit-redux
Fix for https://webarchive.jira.com/browse/ARI-3943
Merge pull request #74 from vonrosen/ari-3943

Fix for https://webarchive.jira.com/browse/ARI-3943
in CrawlURI.createCrawlURI(), avoid clobbering inherited data with data from Link
Merge pull request #75 from nlevitt/uri-inherited-data-fix

in CrawlURI.createCrawlURI(), avoid clobbering inherited data with data ...
Merge branch 'master' into HER-2039

Conflicts:
	modules/src/main/java/org/archive/modules/CrawlURI.java
	modules/src/main/java/org/archive/modules/extractor/ExtractorHTTP.java
	modules/src/main/java/org/archive/modules/extractor/ExtractorSWF.java
	modules/src/main/java/org/archive/modules/extractor/Link.java
	modules/src/main/java/org/archive/modules/writer/WARCWriterProcessor.java
other changes required for merge from master into HER-2039
ensure non-null pathFromSeed to fix some unit tests
copy over and adjust equals(), hashCode(), compareTo() from old Link class to CrawlURI, so that tests pass