Created stable branch for v1.7.
Fixed typo in comment.
Fixed call to triangulate.
Added ability to output area for Green's functions.
test
typos fixed
Fixed typos found by Sue.
fixed typos and format problems
format consistency
Fixed typo.
trivial fixes
backed out of 'ageing' fix made earlier
Fixed typo in rate-state friction equation.
fixed typos and format problems
Fixed typo in label.
typos fixed
fixed typos and format problems