Use selector types in var tokens … Related to #45.

* Fixed selector types in var tokens.
* Changed prettifyValue and getWarnings to use the selector type in var tokens.
Generate var new_tokens which handles additional rules as own block.
Tried to add [ '||', 'rule separator' ] as token.

Changes the result of oh.getOpenIntervals which is wired. Could not find
the reason for this.
API change: Adopted oh.getMatchingRule to work with the new internal structure.
Fixed parseWeekRange to handle syntax 'week :'.
Implemented #45 selector reordering.
Give info to the user that the selector order was changed.
Removed obsolete code.
Merge branch 'selector_array_of_tokens_rework'. Closes #45.

New implementation of prettifyValue() has still some bugs as discover by
`make real_test` which have to be solved later.