Do not save weak references in Network by default (but use them for MagicNetwork)
Allow accessing objects in a Network via a dictionary-style interface, using the object's name
Also add an __iter__ method to support iterating directly over net (instead of iterating over net.objects)
Merge pull request #56 from brian-team/network_access

Network access
Some progress on syntax translation
Always use numerical level values when setting the log levels (otherwise the logging system is broken in Python 2.6). Closes #57
Added AST based parser
Improved printing using precedence for binary operators (but not unary
or boolean)
Removed syntax module and moved ast_parser to brian2.codegen, added
tests
Replaced excepthook which I'd removed by mistake
Merge remote-tracking branch 'origin/master' into language_rewrite
Removed unused languages and replaced sympy with ast_parser
Rewrote Languages to use Jinja2 templates
Do not make test fail if weave is not available (weave does not support Python 3)
BitAnd and BitOr supported (interpreted as logical)
Merge remote-tracking branch 'origin/syntax_translation' into language_rewrite
Added .words attribute to LanguageTemplate
Added dynamic array examples with codegen
Added USE_SPECIFIERS { list of words } to template, and .specifiers
attribute to LanguageTemplate
Better tests and fixed bug with logical operators