Add labels to issue templates

.github/ISSUE_TEMPLATE/i-have-a-question.md

@@ -2,7 +2,7 @@
 name: I have a question
 about: I have a question and don't see a clear answer in documentation
 title: How do I ...
-labels: ''
+labels: Question
 assignees: ''
 
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.github/ISSUE_TEMPLATE/report-package-build-failure.md

@@ -2,7 +2,7 @@
 name: Report package build failure
 about: Let us know about build failures in ports.
 title: "[<port name>] build failure"
-labels: ''
+labels: port bug
 assignees: ''
 
 ---

.github/ISSUE_TEMPLATE/request-a-feature-or-improvement-to-a-port.md

@@ -2,7 +2,7 @@
 name: Request a feature or improvement to a port
 about: Suggest an improvement to one the the ports/libraries in vcpkg
 title: "[<portname>] <short description of feature>"
-labels: ''
+labels: port feature
 assignees: ''
 
 ---

.github/ISSUE_TEMPLATE/request-a-feature-or-improvement.md

@@ -2,7 +2,7 @@
 name: Request a feature or improvement
 about: Suggest an improvement to vcpkg
 title: ''
-labels: ''
+labels: vcpkg feature
 assignees: ''
 
 ---

.github/ISSUE_TEMPLATE/request-a-new-port.md

@@ -2,7 +2,7 @@
 name: Request a new port
 about: Request a new port/library that vcpkg should support
 title: "[New Port Request] <library name here>"
-labels: ''
+labels: new port request - consider making a PR!
 assignees: ''
 
 ---

.github/ISSUE_TEMPLATE/request-an-update-to-an-existing-port.md

@@ -2,7 +2,7 @@
 name: Request an update to an existing port
 about: Let us know about a new version of a library we should pick up.
 title: "[<port name>] update to <version>"
-labels: ''
+labels: port feature
 assignees: ''
 
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