Replace jQuery-migrate with jQuery.browser.
Add functions for detecting whether IE is pre or post 11.

`WYMeditor.isInternetExplorerPre11` and
`WYMeditor.isInternetExplorer11OrNewer`
Initialize IE11 or newer as Gecko.
Fix the IE selection hack in the table plugin for IE11 or newer.
Fix the IE selection hack in the hovertools plugin for IE11 or newer.
Added `WYMeditor.copyPropsFromObjectToObject`
Added stub for support for IE11.
Rewrote WYMeditor.copyPropsFromObjectToObject into a jQuery function.
Fixed Trident 7 class inheritance function stub.
Trident 7 inherits previous Trident's 'keyup' and wrapWithcontainer'.
Seemingly obvious changes to tests upon introduction of IE11 support.
Add comment to existing erroneous code in copy-paste tests.
Don't skip table-insert_in_sublist tests in IE7 and IE8. They pass.

They were failing on me before. I guess IEs are strange...
Update the 'Image insertion outside of a container' test about IE11.
Some comment correction.
More specific jQuery version in bower dependencies.
Add jQuery.browser to bower.json.
Remove vendored jQuery.browser file.
Force and persist bower jQuery version resolution.
Use Grunt to handle bower.