#138 Added basic handling of proposal operation

[Metizik]

General

Closes #138

Added correct handling of fee calculation for Proposal create in SendModal

General

Please make sure the following is done:

• Pull request is onto develop
• If you haven't already, have a look at
  • https://github.com/bitshares/bitshares-ui/blob/develop/CODE_OF_CONDUCT.md
  • https://github.com/bitshares/bitshares-ui/blob/develop/CONTRIBUTING.md

Code Preparation

Please review all your changes one last time before committing

• [x] Check for unused code
• [x] No unrelated changes are included
• [x] None of the changed files are reformatting only
• [x] Code is self explanatory or documented
• [x] All written text is properly translated (english language)

Testing

The branch has been tested on the following browsers (desktop and mobile view)

• [x] Chrome
• [ ] Opera
• [x] Firefox
• [ ] Safari

User interface changes

Delete this section if there weren't any UI changes. Please make sure you tested your changes in all themes

• [ ] Dark
• [ ] Light
• [ ] Midnight

Please provide screenshots/licecap of your changes below

[sschiessl-bcp]

Not working as intended. Switching does not update fee

Will check myself because SendModal is being refactored a bit as we speak

[sschiessl-bcp]

Solution not appropriate, closing.