Prep docs for 1.0 (#94)

### Motivation

Docs were still referencing 1.0.0-alpha.1, but as we're tagging 1.0
soon, update the docs accordingly.

### Modifications

Updated docs.

Also removed the claim that Configuration supports Windows yet, since
our Windows toolchains in CI are crashing when building Configuration.
Once that's fixed and we enable CI, we'll re-add it.

### Result

More accurate docs.

### Test Plan

N/A

Author: czechboy0

Examples/hello-world-cli-example/Package.swift

@@ -10,6 +10,7 @@ let package = Package(
     dependencies: [
         .package(
             url: "https://github.com/apple/swift-configuration",
+            // TODO: Update once 1.0.0 is tagged.
             exact: "1.0.0-alpha.1",
             traits: [.defaults, "CommandLineArgumentsSupport"]
         )

README.md

@@ -59,7 +59,7 @@ If both sources are unavailable, the fallback default of `60` is returned.
 Add the dependency to your `Package.swift`:
 
 ```swift
-.package(url: "https://github.com/apple/swift-configuration", exact: "1.0.0-alpha.1")
+.package(url: "https://github.com/apple/swift-configuration", from: "1.0.0")
 ```
 
 Add the library dependency to your target:
@@ -92,7 +92,7 @@ To enable an additional trait on the package, update the package dependency:
 ```diff
 .package(
     url: "https://github.com/apple/swift-configuration",
-    exact: "1.0.0-alpha.1",
+    from: "1.0.0",
 +   traits: [.defaults, "OtherFeatureSupport"]
 )
 ```
@@ -106,9 +106,9 @@ Available traits:
 
 ## Supported platforms and minimum versions
 
-The library is supported on macOS, Linux, and Windows.
+The library is supported on Apple platforms and Linux.
 
-| Component     | macOS  | Linux, Windows | iOS    | tvOS   | watchOS | visionOS |
+| Component     | macOS  | Linux          | iOS    | tvOS   | watchOS | visionOS |
 | ------------- | -----  | -------------- | ---    | ----   | ------- | -------- |
 | Configuration | ✅ 15+ | ✅              | ✅ 18+ | ✅ 18+ | ✅ 11+   | ✅ 2+    |
 

Sources/Configuration/Documentation.docc/Documentation.md

@@ -152,7 +152,7 @@ These providers can be combined to form a hierarchy, for details check out <doc:
 Add the dependency to your `Package.swift`:
 
 ```swift
-.package(url: "https://github.com/apple/swift-configuration", exact: "1.0.0-alpha.1")
+.package(url: "https://github.com/apple/swift-configuration", from: "1.0.0")
 ```
 
 Add the library dependency to your target:
@@ -179,7 +179,7 @@ To enable an additional trait on the package, update the package dependency:
 ```diff
 .package(
     url: "https://github.com/apple/swift-configuration",
-    exact: "...",
+    from: "1.0.0",
 +   traits: [.defaults, "OtherFeatureSupport"]
 )
 ```
@@ -193,9 +193,9 @@ Available traits:
 
 ### Supported platforms and minimum versions
 
-The library is supported on macOS, Linux, and Windows.
+The library is supported on Apple platforms and Linux.
 
-| Component     | macOS  | Linux, Windows | iOS    | tvOS   | watchOS | visionOS |
+| Component     | macOS  | Linux          | iOS    | tvOS   | watchOS | visionOS |
 | ------------- | -----  | -------------- | ---    | ----   | ------- | -------- |
 | Configuration | ✅ 15+ | ✅              | ✅ 18+ | ✅ 18+ | ✅ 11+   | ✅ 2+    |