support default block_args

Conflicts:
	topaz/parser.py
Support remaining syntax for proc specs
Merge remote-tracking branch 'origin/master' into tim/block_default_args
Merge remote-tracking branch 'origin/master' into tim/Syntax-for-proc-specs
remove docstrings
Merge branch 'tim/Syntax-for-proc-specs' into tim/block_default_args
add tests, remove docstrings
assert result is not None
fix a few docs references to pypy
add File#truncate
add String#reverse
Merge remote-tracking branch 'origin/master' into tim/String#reverse
fix typo
Merge pull request #281 from alex/tim/String#reverse

Add String#reverse
Merge pull request #280 from alex/tim/File#truncate

Add File#truncate
add IO#seek and #rewind
actually flush
Revert "assert result is not None"

This reverts commit 0416ca3ce19b6a2189e22c1f47503ce7878ad9da.
Merge pull request #282 from alex/tim/File#seeking

Add IO#seek and #rewind
fix actual translation error