ncbi_blast_plus: Add macro for specifing num threads.

Inject number of thread dynamically from Galaxy using recent GALAXY_SLOTS implementation.
ncbi_blast_plus: Replace repeated cheetah code related to input files with tool macro.
ncbi_blast_plus: Replace repeated cheetah code related to advanced options with tool macro.
ncbi_blast_plus: Update README to reflect GALAXY_SLOTS changes.
Remove explicit shared_inputs in parallelism definitions.

Since pull request 142, these are no longer needed - anything not split is assumed to be shared.

https://bitbucket.org/galaxy/galaxy-central/pull-request/142/small-task-splitting-simpliciation/diff

Merged 2013-04-04, so already in the stable release of Galaxy.
ncbi_blast_plus: Use newer xml tag for defined XML macros.
ncbi_blast_plus: Refactor requirements and version tags out into shared macros.
ncbi_blast_plus: Create and utilize macro abstraction for advanced options.
ncbi_blast_plus: Reduce duplication in help sections by creating constants for references and output format descriptions.
ncbi_blast_plus: Reduce duplication in help sections by creating constants for FASTA and search time warnings.
ncbi_blast_plus: Create macros for some common parameters.

Namely parse_deflines, max_hits, and filter_queries (one variant).
ncbi_blast_plus: Reduce output handling duplication in cheetah with new @BLAST_OUTPUT@ macro.
ncbi_blast_plus: Use macros to reduce e-value param duplication.
ncbi_blast_plus: Use macros to reduce word-size param duplication.
ncbi_blast_plus: Use macros to reduce strand input param duplication.
Use @BLAST_OUTPUT@ macro in ncbi_psiblast_wrapper.xml
Remove blank lines between XML entries
Define true/false versions of the input_filter_query macro
Bump ncbi_blast_plus to v0.0.22 (more macros and $GALAXY_SLOTS)
Reword @FASTA_WARNING@ macro for use with protein or nucleotide subjects