Prepare for extracting auth-roles from main codebase

- Remove unused classes
- Move BaseHtmlProvider and StreamingBaseHtmlProvider to fcrepo-http-api
** These classes implicitly depend on velocity.properties that is in fcrepo-http-api
- Eliminate dependency of fcrepo-auth-common on fcrepo-http-api
- Move BypassSecurityServletAuthenticationProvider to fcrepo-auth-common
Remove fcrepo-auth-roles-basic and -roles-common

Resolves: https://www.pivotaltracker.com/story/show/74266946
Update fcrepo-build-tools version to match other projects

Resolves: https://www.pivotaltracker.com/story/show/72657116
Resolved merge conflicts.
Added fedorarelsext:hasExternalContent property to fedora:relations CND; re-formatted and sorted fedora:relations block alphabetically; corrected capitalization and changed comments.
Fixed fedorarelsext:hasExternalContent property definition.
Fixed the NPE bug to support the SPARQL str function, and throw NotImplementedException for comparing subject variable value.
Merge pull request #408 from lsitu/feature/sparql_function

Fixed the NPE bug to support the SPARQL str function, and throw NotImplementedException for comparing subject variable value
Lots of content modeling.
Merge branch 'master' into master-aic
Merge branch 'master-aic' of https://github.com/aic-collections/aicdams-lake into master-aic