.sqlproj and datasources.json file parsing (#8921)

* Checkpoint

* Adding mock contents for tree

* added open sqlproj dialog

* reading files from directory

* Added directory traversal

* Adding tree sorting by folder vs file and label

* Improved auto-unfolding of tree based on node type

* replacing fs with fs.promise alias

* PR feedback

* added activation event for when workspace contains sqlproj files

* Returning after displaying error

* Fixing linter errors

* Reworked tree

* Fixing missing grandchildren

* Correcting tree URI construction

* Refactoring to isolate tree item responsibilities from data model responsibilities

* project file parsing

* constructing tree from project files rather than filesystem

* Fixing double-initialization

* Changing projectEntry to take enum for file type

* Correct node type for project item

* Parsing datasources.json

* Child nodes for sql data source

* Localizing strings

* Checkpoint

* Adding mock contents for tree

* added open sqlproj dialog

* reading files from directory

* Added directory traversal

* Adding tree sorting by folder vs file and label

* Improved auto-unfolding of tree based on node type

* replacing fs with fs.promise alias

* PR feedback

* added activation event for when workspace contains sqlproj files

* Returning after displaying error

* Fixing linter errors

* Reworked tree

* Fixing missing grandchildren

* Correcting tree URI construction

* Refactoring to isolate tree item responsibilities from data model responsibilities

* project file parsing

* constructing tree from project files rather than filesystem

* Fixing double-initialization

* Changing projectEntry to take enum for file type

* Correct node type for project item

* Parsing datasources.json

* Child nodes for sql data source

* Localizing strings

* missed file in merge

* changed extension method to helper

* cleanup

* Adding docstrings

extensions/sql-database-projects/yarn.lock

@@ -18,6 +18,18 @@
     esutils "^2.0.2"
     js-tokens "^4.0.0"
 
+"@types/node@*":
+  version "13.1.2"
+  resolved "https://registry.yarnpkg.com/@types/node/-/node-13.1.2.tgz#fe94285bf5e0782e1a9e5a8c482b1c34465fa385"
+  integrity sha512-B8emQA1qeKerqd1dmIsQYnXi+mmAzTB7flExjmy5X1aVAKFNNNDubkavwR13kR6JnpeLp3aLoJhwn9trWPAyFQ==
+
+"@types/xml2js@^0.4.5":
+  version "0.4.5"
+  resolved "https://registry.yarnpkg.com/@types/xml2js/-/xml2js-0.4.5.tgz#d21759b056f282d9c7066f15bbf5c19b908f22fa"
+  integrity sha512-yohU3zMn0fkhlape1nxXG2bLEGZRc1FeqF80RoHaYXJN7uibaauXfhzhOJr1Xh36sn+/tx21QAOf07b/xYVk1w==
+  dependencies:
+    "@types/node" "*"
+
 ansi-styles@^3.2.1:
   version "3.2.1"
   resolved "https://registry.yarnpkg.com/ansi-styles/-/ansi-styles-3.2.1.tgz#41fbb20243e50b12be0f04b8dedbf07520ce841d"
@@ -192,6 +204,11 @@ resolve@^1.3.2:
   dependencies:
     path-parse "^1.0.6"
 
+sax@>=0.6.0:
+  version "1.2.4"
+  resolved "https://registry.yarnpkg.com/sax/-/sax-1.2.4.tgz#2816234e2378bddc4e5354fab5caa895df7100d9"
+  integrity sha512-NqVDv9TpANUjFm0N8uM5GxL36UgKi9/atZw+x7YFnQ8ckwFGKrl4xX4yWtrey3UJm5nP1kUbnYgLopqWNSRhWw==
+
 semver@^5.3.0:
   version "5.7.1"
   resolved "https://registry.yarnpkg.com/semver/-/semver-5.7.1.tgz#a954f931aeba508d307bbf069eff0c01c96116f7"
@@ -254,3 +271,16 @@ wrappy@1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/wrappy/-/wrappy-1.0.2.tgz#b5243d8f3ec1aa35f1364605bc0d1036e30ab69f"
   integrity sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8=
+
+xml2js@^0.4.23:
+  version "0.4.23"
+  resolved "https://registry.yarnpkg.com/xml2js/-/xml2js-0.4.23.tgz#a0c69516752421eb2ac758ee4d4ccf58843eac66"
+  integrity sha512-ySPiMjM0+pLDftHgXY4By0uswI3SPKLDw/i3UXbnO8M/p28zqexCUoPmQFrYD+/1BzhGJSs2i1ERWKJAtiLrug==
+  dependencies:
+    sax ">=0.6.0"
+    xmlbuilder "~11.0.0"
+
+xmlbuilder@~11.0.0:
+  version "11.0.1"
+  resolved "https://registry.yarnpkg.com/xmlbuilder/-/xmlbuilder-11.0.1.tgz#be9bae1c8a046e76b31127726347d0ad7002beb3"
+  integrity sha512-fDlsI/kFEx7gLvbecc0/ohLG50fugQp8ryHzMTuW9vSa1GJ0XYWKnhsUx7oie3G98+r56aTQIUB4kht42R3JvA==