Document --2.0 flag.
Minor output tweak
added docu for building distributions [skip ci]
added docu for building ALL distributions [skip ci]
JRUBY-7190:  Incorrect encoding on result string read from File introduced in JRuby 1.7.4
Fix typo in testing documentation
Merge pull request #943 from Sinjo/fix_test_docs_typo

Fix typo in testing documentation
start using Joda's DateTime in lib/date.rb

* Tests are unaffected by this change.
* Zone offset and Gregorian cutover are computed from the DateTime.
* They are still copied in instances variables for ease of compatibility with current code.
* @ajd need to be preserved for now as DateTime only has millisecond precision,
  date.rb has arbitrary (although mentioned not expected > ns) (via Rational).
* Joda methods are used for year,week,day,hour,min and second
  (but not fractions since it might be imprecise).
use RubyDateFormat to format Date, yeah!
add formatting letters in javadoc to RubyDateFormat formats
add missing format %g (short weekyear) to RubyDateFormat
fix RubyDateFormat %c, blank-padded day, not zero-padded
fix RubyDateFormat FORMAT_CENTURY: use getYear() so it does not depend on Chronology

* In ISOChronology, it is fine, but in GJChronology, it's century + 1.
* Still a problem for the year right now with GJChronology (but no test!)
RubyDateFormat: handle ignored POSIX modifiers as MRI
handle extra date formats in RubyDateFormat
raise an ArgumentError when millis is a Bignum as Joda cannot support such "times"

* that is earlier than 25e15 BC or later than 25e15 AD ...
fix logic for Date#year: should add 1 only during JulianChronology (before @sg)
Date#rfc3339 is now defined as strftime('%FT%T%:z')
%v in Time is %e-%^b-%Y and is %e-%b-%Y for Date/DateTime
handle %L as a special case of %N and fix 1.8/1.9 conditions