fix(demo): Fix build issues

[Logikgate]

Demo build issues

1. Input-mask's PodFile was forcing all pods to be compiled with swift 4.0 but camera-plus requires swift 4.2.
2. app.demo.clean and just running npm i manually within the demo folder was failing with this error:
   
3. The demo file for camera-plus had type errors in it introduced by the merge of pull request Updates camera-plus #23

Fixes

1. Modified input-mask's PodFile to only affect the InputMask pod.
2. Changed the demo's devDependency of typescript to pin it to ~4.0.3 instead of pulling from the parent node_modules. I'm unsure why this was necessary though, if you have any idea how to make the relative path work please let me know 😀
3. Modified the demo file for camera-plus to fix the type errors.

[NathanWalker]

nativescript-input-mask published with this fix in 0.1.1