docs: add extra remarks and troubleshoot section

[devrnt]

Add extra remarks about IntercomProvider and useIntercom. Add "troubleshoot" section in readme.

• IntercomProvider should be placed as high in the tree as possible.
• useIntercom can't be called in the same component where IntercomProvider was initialized.
• Add "Troubleshoot" section in readme. This will keep track of some common occured "problems/issues"

Closes #13

[github-actions]

Size Change: 0 B

Total Size: 9.35 kB

ℹ️ View Unchanged

Filename	Size	Change
dist/index.js	152 B	0 B
dist/react-use-intercom.cjs.development.js	3.53 kB	0 B
dist/react-use-intercom.cjs.production.min.js	2.25 kB	0 B
dist/react-use-intercom.esm.js	3.42 kB	0 B

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