Improvement with DHCP

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### Prerequisites

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- [X] I am running the latest version
- [X] I checked the documentation and found no answer
- [X] I checked to make sure that this issue has not already been filed

### Problem Description
Improvements to be made for DHCP:
- allow client creation from the DHCP page or alternatively from the Client page with list of MAC address / name of devices. It is currently overcomplicated to create clients with their MAC address, you have to copy MAC address from one page to the other
- default creation of rules "block/allow this address for this client" based on the name of the device (and not the IP address) to deal with dynamic lease
- have two buttons for DHCP flushing : one for dynamic and one for static leases

### Proposed Solution

### Alternatives Considered

### Additional Information