Add tool UrlSamplerHost:

- sample URLs based on limits per host (without leading www.)
- variant of UrlSampler (per-domain limits)

Add tool UrlSamplerHost:

- sample URLs based on limits per host (without leading www.)
- variant of UrlSampler (per-domain limits)

WarcCdxWriter: normalize URL of redirect target location

Convert the redirect target location into an absolute URL
and normalize the URL using the URL normalizer configured
for scope "fetcher" before storing it as field "redirect"
in the CDX file.

Create all instances of SimpleDateFormat using the ROOT
locale, use timezone "UTC" consistently.

WarcCdxWriter: normalize URL of redirect target location

Convert the redirect target location into an absolute URL
and normalize the URL using the URL normalizer configured
for scope "fetcher" before storing it as field "redirect"
in the CDX file.

Create all instances of SimpleDateFormat using the ROOT
locale, use timezone "UTC" consistently.

Merge upstream branch 'master' into cc

Merge upstream branch 'master' into cc

NUTCH-3072 Fetcher to stop QueueFeeder if aborting with "hung threads"

- fix typo in counter name

Merge upstream branch 'master' into cc

Notable changes (speed up of unit tests):
- NUTCH-2771 Tests in nightly builds: skip long runners
- NUTCH-3084 Improve CI by filtering and separating plugin
  and core test execution

Merge branch 'NUTCH-3067' into cc

cf. https://issues.apache.org/jira/browse/NUTCH-3067

Merge pull request #30 from commoncrawl/cc-http2

WARC writer support HTTP/2