Improve english suffix rules

Rewrite suffix rules using regular expressions for readability and extensibility, and expand coverage to all suffixes
Reorder rules by specificity (fixes problem with y+... -> i+... blocking y+s -> ies)
Improve suffix rule detection
...ue has a silent e
inch + s = inches
simplify plural rules, add nudzhes
apply rules to multi-word suffixes like 'ing in' or 'ly is'
a better (working) way to implement multi-word suffixes
belches
patriarchied
wearisome (oops)
remove y+i->i rule as it causes too many problems
Add unit tests. All pass or are marked as TODO.
Small fixes to make Github README page look better.

I'm using RST chapters and section to add some style to the project
front page on Github.
allow {^ing Mc^} to work as expected
[BIG] Enforcing PEP8 on the plover/ files.

A few fixes here and there:
- lines < 80char
- spaces around operators
- unused imports and variables
- `duck` replaced with repr(duck)
- comparisons with None, True, False, replaced with "is", "is not"
Adding empty changelog to fix #17.
Merge pull request #67 from mike-perdide/cosmetic_readme

Small fixes to make Github README page look better.
Merge pull request #68 from mike-perdide/pep8_fixes

[BIG] Enforcing PEP8 on the plover/ files.
Merge pull request #69 from mike-perdide/add_changelog

Adding empty changelog to fix #17.