Several extensions are broken with latest Theia

[svor]

che-theia-task extension error log:

src/browser/che-task-provider.ts(30,19): error TS2322: Type '{ type: "che"; label: string; command: string; target: { machineName: string | undefined; }; previewUrl: string | undefined; }' is not assignable to type 'CheTaskConfiguration'.
  Property 'source' is missing in type '{ type: "che"; label: string; command: string; target: { machineName: string | undefined; }; previewUrl: string | undefined; }'.
src/browser/che-task-resolver.ts(57,15): error TS2322: Type '{ type: "che"; label: string; command: string; target: Target; previewUrl: string | undefined; }' is not assignable to type 'CheTaskConfiguration'.
  Property 'source' is missing in type '{ type: "che"; label: string; command: string; target: Target; previewUrl: string | undefined; }'.

che-theia-remote-extension error log:

lerna ERR!   Property 'getExtraPluginMetadata' is missing in type 'ServerPluginProxyRunner'.

Also che-theia-terminal extension is broken: #29