Added syntax highlighting for *.tpl / *.twig files

*.tpl / *.twig files are Smarty / Twig templates and should be treated as HTML files.
Remove cruft from the outdated stats-gathering branch.
Added code to return tagName when in closing tag
A few refactorings
Fixes after first review
Fixes after second review
Initial test files creation
First pass at popover styles.
Update UI
Merge branch 'glenn/hover-preview-ui' of github.com:adobe/brackets into glenn/hover-preview-ui
Rebasing
fixed padding
Increase max image size to 200x200
Add unit tests for hover preview
Adding image files used in unit tests
cleanup based on codereview comments:

Update jsdoc
use ExtensionUtils.getModulePath instead of manually slicing up path
use FileUtils.readAsText instead of DocumentManager when we only need the text on disk
Call CollectionUtils.hasProperty instead of Object.prototype.hasOwnProperty...
Add comment explaining logic around finding location of called function for function type hinting
remove unnecessary calls to setCursorPos
remove stale comments in unittests
pull out hint invalidation check into a function and remove check for query.length === 0, not necessary anymore
define offset in constant
Merge pull request #3472 from adobe/glenn/hover-preview-ui

Update Hover Preview UI for final design
Externalize strings from Extension Manager view item template
Updated by ALF automation.
Explain whether incompatible extensions require older or newer versions of Brackets. Remove hard-coded app name references in strings.