Merge branch 'stack-frames' of github.com:BaseXdb/basex into stack-frames
Merge pull request #635 from LeoWoerteler/stack-frames

More index rewritings and some refactoring.
Merge branch 'stack-frames' of github.com:BaseXdb/basex into stack-frames
Merge pull request #636 from LeoWoerteler/stack-frames

Finalizing the stack-frames branch.
[MOD] Commands, Add: Prop.ADDCACHE added to enforce caching of new docs
[MIN] BaseXHTTP: server ping timeout increased
[MOD] GUI, Editor: improved highlighting of XML documents
[MIN] highlighting of first character in processing instruction
[MIN] Documentation converted to HTML format
[FIX] XQuery, importing module: disallow duplicate namespace prefixes
[ADD] XQuery: prof:swallow($value) swallows the specified sequence.
      http://docs.basex.org/wiki/Profiling_Module#prof:swallow
[MIN] XQuery: prof:swallow() renamed to prof:void()
[MIN] XQuery: prof:swallow() renamed to prof:void()
Merge branch 'master' of github.com:BaseXdb/basex
[MIN] XQuery: moving check for duplicate namespace declarations
[MIN] XQuery: materialize results swalloed by prof:void()
[FIX] DBLocking: NPE fix
[MOD] Core, locking: downgrade function added to Locking interface
[MIN] comment
[MIN] XQuery, prof:void() signature fixed