2.3 Beta Release

Most notably, added auto-completion functionality in all editors.
Reworked the name cache with efficiency in mind and prevented
unnecessary queries when saving new cache entries.

Also reduced over all global footprint in JavaScript, using a modular
approach with only one global variable, MentionMe.

Added the option to minify JS and added minified JS files to core
package as well as wrangled all of MentionMe's JS into one folder.
Ammendment for ba0bb51035

Omitted cursor position library by @kir
https://github.com/kir/js_cursor_position
Addressing #46

. . . where failure to declare local variables polluted the global
scope.
Addressing #47

. . . where pressing the ENTER key prematurely dismissed the popup
completely. Added a check for the cache loading indicator before
dismissal.
2.3 Pre-release

versioning and readme update
Merge pull request #48 from WildcardSearch/minor

2.3 Release