Fix javadoc in ConfigRenderOptions.setFormatted

It looks like this was copied from setComments and one bit wasn't changed.
Merge pull request #197 from chris-martin/ConfigRenderOptions-setFormatted-javadoc

Fix javadoc in ConfigRenderOptions.setFormatted
typo: "will (now -> not) throw"
Merge pull request #198 from chris-martin/typo_now-not

typo: "will (now -> not) throw"
README: show how to do "inheritance" on one line
add badge + link to maven central
Merge pull request #200 from tyrcho/patch-1

add badge + link to maven central
README: link to maven central directory

Fixes #203, linking to super-old releases was just confusing.
Add profiling of getting values from a Config

To run these, do
> project config
> test:runMain GetExistingPath
> test:runMain HasPathOnMissing
> test:runMain CatchExceptionOnMissing
Use nanotime for profiling and use more iterations

This doesn't make the benchmarks all accurate or anything
but maybe makes them a little less likely to be way off.
Change CatchExceptionOnMissing bench to have more stack frames
Avoid PathBuilder for fast-path path parsing

This makes the typical path parse much faster:
 - avoid Character.isLetter in favor of just ASCII alphanumeric
 - allow fast path with hyphens and underscores involved
 - don't use PathBuilder, build a Path directly by
   traversing the string backward; this avoids some
   object allocation
README: recommend hasPath rather than catching Missing
Merge remote-tracking branch 'origin/master' into wip/havocp-resolve-fixes
Make ResolveContext immutable

This is a mechanical refactoring not intended to change behavior.
Not very efficiently implemented but that's fine for now.
Move ResolveSource into ResolveContext again

Now that ResolveContext is immutable and passed back
from each resolve step, we move the immutable ResolveSource
back into it. This will allow resolve steps to modify
the ResolveSource in ways that affect subsequent resolve
steps, if we want.