Make the default mappings optional
Change formatting of SETTINGS help section
Merge pull request #7 from michamos/no-mappings

Make the default mappings optional
Fix help tags missed from copy/paste
Mention use of visual mode in help and README
Answer some FAQs in the README
Use getregtype() to restore register's mode.
Use setreg() to preserve yanked text's -wise mode
Merge pull request #9 from Raimondi/patch-1
Use " register instead of @
Use getreg() instead of macro syntax
Fix quoting for escaped <C-V> sequence

This bug would probably have never affected anyone, since it only
comes up when a normal-mode motion results in a blockwise selection.
Detect overlap for two blockwise regions
Allow default mappings to be overridden

Partial solution to #11
Add documentation for overriding maps
Explain issue #11 caveat and solutions in README
Fix incorrect visual mapping to cxx

Fixes #12.
Change <Plug> mappings to avoid prefix strings

Any custom mappings to <Plug>Exchange, <Plug>ExchangeLine, or
<Plug>ExchangeClear will have to be changed to map to <Plug>(Exchange),
<Plug>(ExchangeLine), and <Plug>(ExchangeClear).

References #12
Link to Wiki from README
Highlight the first defined exchange region

Closes #13.