#3 Make Caching site specific property

[Dmitri]

Although no caching while spidering is probably the
best, sometimes it is preferred to use cache. I
suggest making cache site configuration parameter.
Attached you will find 5 files implementing this feature.
By default cache is DISABLED and cache param set to
no-cache, but it can be enabled per-site.

[Dmitri]

[Dmitri]

[Dmitri]

[Dmitri]

[Dmitri]

[EJP]

This patch also requires adding the following to SpiderContextImpl.registerNewSite(), after all the other 'sitei' configurations:

    sitei.setCacheControl(siteProps.getString(ConfigConstants.SITE_CACHE_CONTROL, Constants.CACHE_CONTROL));
    sitei.setUseCache(siteProps.getBoolean(ConfigConstants.SITE_CACHE_USE, false));

[EJP]

This patch also requires adding the following to SpiderContextImpl.registerNewSite(), after all the other 'sitei' configurations:

    sitei.setCacheControl(siteProps.getString(ConfigConstants.SITE_CACHE_CONTROL, Constants.CACHE_CONTROL));
    sitei.setUseCache(siteProps.getBoolean(ConfigConstants.SITE_CACHE_USE, false));