Adding condition for skipping symlinks when installing extensions via the extension manager

When installing extensions that have symlinks via the extension
manager, they will fail with a message regarding an invalid zip file.
This can be tested with
https://github.com/MiguelCastillo/Brackets-SymbolicLinks
close dropdown on inline editor close or editor resize
change build.prop to (1) work when on a detached head during jenkins build (2) use bash compatible property key names and (3) include shell git info
use ls-remote to compare HEAD and then reflog as a backup
fix returning reflog promise
* Whole bunch of docs clarifications & type-annotation fixes
* Clarify Save As dialog cancelation handling -- and fix bug where promise
was never resolved in degenerate doSave() case
* Improved some console messages: more explanatory KeyBindingManager error,
more info on Directory exceptions, clarify consequence of LanguageManager
error
* Fix misleading use of "document" in Close Others API & related code naming
* Improve docs for adding new locale translations
allow shell git info to be optional
Merge branch 'master' into jasonsanjose/build-prop-keys
Merge branch 'master' into jasonsanjose/build-prop-keys
build-config task to be used by concat/minify build process
added pointer-events to CSS Code Hints
use capture event handler
Add css property filter in CSSCodeHints/CSSProperties.json
Merge branch 'master' into MiguelCastillo-master
Merge pull request #6116 from adobe/pflynn/small-cleanups

Minor code cleanups, docs improvements, console message clarifications
Revert "use capture event handler"

This reverts commit 65cc4dde48752208ac7308a08945e90bfa4a2d7d.
Merge pull request #6056 from adobe/randy/issue-6005

Close New Rule dropdown on inline editor close or editor resize
Merge pull request #6076 from adobe/jasonsanjose/build-prop-keys

Changes to build.prop file to support Jenkins jobs
Adds a test for files with symlinks
Merge branch 'MiguelCastillo-master' (PR #5919)