added swp files to gitignore
Added BaseInfoTrait, improved FieldInfo.

Added a new BaseInfoTrait which is the super trait for MethodInfo,
FieldInfo and ClassInfo. This allows the nice modifier convenience
methods to be used on all three. Added descriptors and initial
value fields to FieldInfo. Removed overridden toString and hashCode
from FieldInfoImpl as not necessary.
added synthetic modifier to list of modifiers
Fixed ClassInfo signature.

Now consistent with Method and Field signature: empty string
or actual signature.
Added isSynthetic convenience method.
trimmed whitespace off of end of lines
Merge pull request #13 from jcrussell/master

Added BaseInfoTrait, improved FieldInfo.