Minor wording edits

Note that this includes a change from a double-dash to an actual, unicode
em-dash.
Minor wording edits to getting-started section.

Note that a triple-dash was replaced with a unicode em-dash.
Wrap long line and clarify reference to demo
Edits to data-format and pipelining sections

- Minor rewording
- Label scikit-learn separately from link (for consistency with other parts of the paper
- Labeling of signed and unsigned images flipped
Edits to research-usage section

- "datatype" -> "data-type" (for consistency with other parts of the paper)
- "file formation" -> "file format"
- Reword description of crack-data extraction
- Add double back-ticks around ``measure.profile_line``
Minor rewording of education-usage sentence
Edits to Panorama stitching example

- Minor wording edits at the top of this section.
- Change uppercasing from "SAMple" to "SAmple" on (RANSAC)
- Remove errant comma
- Move `SimilarityTransform` import down to appropriate block of code
- Reformat alpha-channel function for readability
Add missing word ('mask')

Also, format lines so it's easier to pick out the diff from master
Merge pull request #48 from tonysyu/edits/panorama

Edits to Panorama stitching example
Merge pull request #47 from tonysyu/edits/usage-education

Minor rewording of education-usage sentence
Merge pull request #44 from tonysyu/edits/getting-started

Minor wording edits to getting-started section.
Merge pull request #46 from tonysyu/edits/usage-research

Edits to research-usage section
Merge pull request #45 from tonysyu/edits/data-format-and-pipelining

Edits to data-format and pipelining sections
Merge pull request #43 from tonysyu/edits/introduction

Minor wording edits to introduction section