v0.6.1

I forgot to merge develop into master for the 0.6.0 release, so actually all of the contents of 0.6.0 are now in the 0.6.1 release. So again:

NOTE: This release has breaking changes for the annotations language. Namely, the deprecated annotations without a '#' before the first word will now be IGNORED and only a warning will be issued when they are detected. (i.e. /// if_succeeds true will be ignored)

This release contains the following fixes:

Add precaution message at the top of instrumented files, "not to be modified manually"
#125 Change behavior to ignore annotations without a "#" and just issue a warning
#67 Support property specifications in custom NatSpec tags (@custom:scribble #if_succeeds...)
Initial support for scribble macro yaml files