Uses table alias in WHERE

If a table alias is used for the main table, it's not valid according
to the SQL standard to refer to it by it's "real name" (see
http://www.postgresql.org/docs/8.2/static/queries-table-expressions.html
#QUERIES-TABLE-ALIASES). This causes problems when doing JOIN with a
table alias for the "main table", since previous code always used table
name. Now, we check for a table alias.
Corrects typo in "testJoinWithAliasesAndWhere" method name.
Merge branch 'vicvicvic-wherealias' of https://github.com/vicvicvic/idiorm into develop