cmake: Increase FFTW timeout.

Signed-off-by: Matthew Emmett <memmett@gmail.com>
doc: Formatting and tweaks to style guide.

Of particular note:

1. I added two exceptions regarding template parameter names: `scalar` and
   `time` don't need a T.

2. I removed `m_` from class variables.

Signed-off-by: Matthew Emmett <memmett@gmail.com>
doc: Formatting.

Signed-off-by: Matthew Emmett <memmett@gmail.com>
Merge branch 'master' of github.com:Parallel-in-Time/PFASST