Add missing titles to few docs to make sure they're rendered in docs.
Fix import statements.
Sublists must have blank lines before and after.
Fix "title underline too short" warnings.
Fill in required explicit argument for code-block.
Add docstring documentation to all llvm.core classes.

Some classes have docstrings, and lack rST docs (e.g. Module), few others
vice versa. It's unclear what is the best way to deal with this. IMHO,
docstrings should prevail, i.e. existing docs would rather be moved
to docstings. Anyway, for now just make sure that users don't miss
documentation, even if it's just list of classmembers.
Allow Sphinx build docs with docstrings without installing module.
Merge branch 'docs-fixes' of github.com:pfalcon/llvmpy into _pr57
Modified documentation configuration to search for build specific to Python version.  Updated copyright.  First attempt at using llvm._version to set documentation version.