Update plugin build scripts

Based on OBS plugin template build scripts with some minor adjustments:

 * Adjust format check scripts to exclude ./deps folder
 * Adjust release scripts to only draft releases
 * Always build installers
 * Always upload build artefacts
 * Build opencv for Mac and Windows releases

cmake/bundle/windows/installer-Windows.iss.in

@@ -0,0 +1,63 @@
+#define MyAppName "@CMAKE_PROJECT_NAME@"
+#define MyAppVersion "@CMAKE_PROJECT_VERSION@"
+#define MyAppPublisher "@PLUGIN_AUTHOR@"
+#define MyAppURL "http://www.mywebsite.com"
+
+[Setup]
+; NOTE: The value of AppId uniquely identifies this application.
+; Do not use the same AppId value in installers for other applications.
+; (To generate a new GUID, click Tools | Generate GUID inside the IDE.)
+AppId={{CD703FE5-1F2C-4837-BD3D-DD840D83C3E3}
+AppName={#MyAppName}
+AppVersion={#MyAppVersion}
+AppPublisher={#MyAppPublisher}
+AppPublisherURL={#MyAppURL}
+AppSupportURL={#MyAppURL}
+AppUpdatesURL={#MyAppURL}
+DefaultDirName={code:GetDirName}
+DefaultGroupName={#MyAppName}
+OutputBaseFilename={#MyAppName}-{#MyAppVersion}-Windows-Installer
+Compression=lzma
+SolidCompression=yes
+
+[Languages]
+Name: "english"; MessagesFile: "compiler:Default.isl"
+
+[Files]
+Source: "..\release\*"; DestDir: "{app}"; Flags: ignoreversion recursesubdirs createallsubdirs
+Source: "..\LICENSE"; Flags: dontcopy
+; NOTE: Don't use "Flags: ignoreversion" on any shared system files
+
+[Icons]
+Name: "{group}\{cm:ProgramOnTheWeb,{#MyAppName}}"; Filename: "{#MyAppURL}"
+Name: "{group}\{cm:UninstallProgram,{#MyAppName}}"; Filename: "{uninstallexe}"
+
+[Code]
+procedure InitializeWizard();
+var
+  GPLText: AnsiString;
+  Page: TOutputMsgMemoWizardPage;
+begin
+  ExtractTemporaryFile('LICENSE');
+  LoadStringFromFile(ExpandConstant('{tmp}\LICENSE'), GPLText);
+  Page := CreateOutputMsgMemoPage(wpWelcome,
+    'License Information', 'Please review the license terms before installing {#MyAppName}',
+    'Press Page Down to see the rest of the agreement. Once you are aware of your rights, click Next to continue.',
+    String(GPLText)
+  );
+end;
+
+// credit where it's due :
+// following function come from https://github.com/Xaymar/obs-studio_amf-encoder-plugin/blob/master/%23Resources/Installer.in.iss#L45
+function GetDirName(Value: string): string;
+var
+  InstallPath: string;
+begin
+  // initialize default path, which will be returned when the following registry
+  // key queries fail due to missing keys or for some different reason
+  Result := '{autopf}\obs-studio';
+  // query the first registry value; if this succeeds, return the obtained value
+  if RegQueryStringValue(HKLM32, 'SOFTWARE\OBS Studio', '', InstallPath) then
+    Result := InstallPath
+end;
+