fixes due to oligomask

added internal function read.database.tables
added test.db.2 and accompanying tests to the unit tests
started oligomask specific unit test
bug fixes to join method

the join method was modified to deal with more complicated
schemas--testing needed before merging with master.
bug fixes

-Fixed issue with specifying multiple cols in a single table in 'select'
-improvements/bugfixes to 'join' for branched schemas.
-bumped version to 0.99.9
bug fixes

-fixes  to join and get.join.keys to address issues with branched
queries.
-added additional unit test
-bumped version number
Bugfixes

Fixed bugs in join concerning select statements over branched queries.
Fixed bug in select when specifying a mixture of table.column and
column only queries.
select should also return columns in the specified order when
appropriate
Added a test case for the mixed table.column, column queries over the
oligoMask example
Bumped version number
Merge branch 'working'