BaseParser: fix hexDigit{,UpperCase}() :/

Were missing 3!

Was not missing in hexDigitLowerCase() though.
Complete release notes
1.0.0-beta.3
Announce 1.0.0-beta.3 -- brown paper bag release, yay
CustomDefaultLabelMatcher: make public
Preliminary version of JoinMatcher
JoinMatcher: some modifications

Matching not written etc.
JoiningRuleBuilder: implement min(), max(), times()
Modify Join{ed,ing}RuleBuilder

Make JoinedRuleBuilder accept a BaseParser as an argument so that it can use its
.toRule().
OneOrMoreMatcher: skip test for empty match

The CanMatchEmptyVisitor has already taken care about that.
Revert "OneOrMoreMatcher: skip test for empty match"

This reverts commit 35119aab5491906920df6b8b3ba5b5de781cbdff.

It appears that this test is done in each and every matcher _in addition_ to the
CanMatchEmptyVisitor.

There needs to be a way to detect that earlier so that such a test does not have
to be done at "parsing runtime"!
JoiningRuleBuilder: add .range() method

Takes a Guava Range as an argument. Sanity tests. But not tested yet...
OneOrMoreMatcher: skip test for empty match -- again

We assume that the CanMatchEmptyVisitor test is enough
More code for JoiningRuleBuilder, and start tests