Add sources.
Reduce dependancies of post and pre.
Create .gitignore.
-ftemplate-depth=256 for all build types.
Compilation stuff.

At linkage, visibility was set to hidden, which caused warnings. Must
investigate if it's a real problem or not.
Also, link with Boost.System, otherwise linkage fails under Mac OS X
using Boost 1.55.
Places can now be created even if they only appear in transitions.
Change linkage order of Boost libraries.
Add a BPN (from CADP) parser. The correct parser must now be specified at runtime.
Reorganize samples.
Detect dead transitions.
New BPN sample
Remove arc types.
Hand-written parser for TINA format.

Get rid of one of the two boost::spirit dependencies. Some features are still lacking, like ‘’K on markings and other arc types.
Create a file for parse_error exception.
More robust BPN parse.
A parse_error can now be constructed with a message.
Add some diagnostic messages for the TINA parser.
Check that ‘->’ is present in a TINA transition.
Result of peek() is not a char, but an int_type.
Whitespaces.