Merge pull request #4 from silverstripe-big-o/boost

NEW Added search-time boost support to SolrIndex
Merge pull request #5 from silverstripe-big-o/excludevariantstate

NEW SearchIndex->excludeVariantState()
Merge pull request #6 from silverstripe-big-o/ignore-empty-fields

Ignore empty fields
Merge pull request #8 from silverstripe-big-o/pull/docs-types

Docs about custom types
Merge pull request #12 from silverstripe-big-o/pull/custom-source-paths

ENHANCEMENT Configurable source paths for Solr config
Merge pull request #13 from silverstripe-big-o/pull/spell-checking

ENHANCEMENT Better spell checking default config and docs
Merge pull request #14 from silverstripe-big-o/pull/instance-of-sslist

BUG Check for instanceof SS_List rather than deprecated DataObjectSet
Add composer file
Fixing missing backtick to indicate code formatting
removing experimental notes in docs
Logging Solr communication exceptions as warnings

Before we didn't catch exceptions, the CMS would break when communication
errors with Solr occurred, this change will log those exceptions as warnings
so that creating new and publishing pages will continue gracefully.
Additional docs on specifying search fields and boosting
If no remote dir set for WebDAV, just use the index name by itself
WebDAV::exists() should add a trailing slash for checking dirs

Without it, some WebDAV servers will thrown an error.
Better checking for permissions when running Solr_configure
Ensure all cores are initialised on configure
NEW Add variant for regular subsite module.
fixing broken Solr_configure
Merge branch 'pull/custom-query-params' of github.com:silverstripe-big-o/silverstripe-fulltextsearch into silverstripe-big-o-pull/custom-query-params
Merge branch 'pull/highlighting-support' of github.com:silverstripe-big-o/silverstripe-fulltextsearch into silverstripe-big-o-pull/highlighting-support