Finished the GC section. Removed all but one XXX. Replaced 1.6 with 2.0. Various minor corrections and additions.
Finished the GC section.
Removed all but one XXX.
Replaced 1.6 with 2.0.
Various minor corrections and additions.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator