Edge case handling for increases in edge length

[Thunder2103]

Need to implement conditions in case an edges increase in length causes a node to be pushed off screen.

Notes:

• Add a force to pull nodes to center of screen
• Push other node if one is going to go off screen or push both nodes when edges expands

[Thunder2103]

An easier solution is placing the node back on screen then moving the other node and edge by the same amount the off screen node was moved to preserve the edges length