Allow running tools on multiple datasets simulatenously (UI).

Update tool form. This commit needs work to ensure this only affects the tool_form.mako.
Add tool meta parameter exception.
Parallel tool execution across dataset collections (backend).
Parallel tool execution across dataset collections (UI).
Implicit creation of analogous dataset collections...

... when running normal tools with normal data inputs across dataset collections in parallel. A previous changeset added the ability to run the tool in parallel - this changeset extends that functionality to create analogous collections from these parallel runs.

For example, if one filters a pair of FASTQ files a pair is created out of the result. Likewise, if one filters a list of FASTQ files - a list collection with same cardinality is built from the results.

There is a lot left TODO here - for one a lot of this logic should be moved into the dataset_collection module. The matching needs to be exact right now - not a problem for pairs (every 'element' has name 'left' or 'right') but for lists with element names - these have to match exactly - but a 'list' like samp1_l, samp2_l, samp3_l should be able to match against samp1_r, samp2_r, samp3_r and create a new list samp1, samp2, and samp3. Even if there is no matching prefixes a new 'unlabeled' list should be able to be created.
Refactor workflow module to allow multiple kinds of inputs.
Add history.active_contents property...

Get all active datasets and collections ordered together by hid.
Handle dataset collections in workflows.

Extend workflow running, extraction, viewing to allow tools with data_collection parameters.

This is brutally ugly because "isinstance( input, DataToolParameter )" which was already not very Pythonic has been updated to be "isinstance( input, DataToolParameter ) or isinstance( input, DataCollectionToolParameter )". This should all be reworked with an "is_data_parameter" on base ToolParameter.