add ExtractLinks and PrefixQuery(ExtractSiteLinks)
update README file, add steps for getting URLs and extracting links
trival update Readme file, modify format
add Lucene FST prefix search
More work on Issue #22: prev/next buttons turns on and off appropriately.
Fixes for Issues #18, #21, #22
add prefix search feature to UriMapping class; add test class for UriMapping PrefixSearch
remove TestFSTPrefix class
Merge branch 'extract-links' of github.com:Jeffyrao/warcbase into fst

Conflicts:
	src/main/java/org/warcbase/data/UriMapping.java
Light refactoring, fixed a few errors.
Exposed -getPrefix command-line option.
Updated documentation.
Fixed Issues #16, #19, #23
add extract site-level links
Update README.md
Update README.md
add ExtractSiteLinks in pom.xml
Tweaked README.
Fixed Issue #13
Merge branch 'master' of github.com:milad621/warcbase into display_issues