leaflet绘制圆形方案

电子围栏绘制方案：

1. 采用leaflet绘制电子围栏 可以看对应api文档 。
2. 原生是英文，所以要重定义，直接覆盖下面的 leaflet.draw-cn.js 文件

3. L.drawLocal = {
   	draw: {
   		toolbar: {
   			// #TODO: this should be reorganized where actions are nested in actions
   			// ex: actions.undo  or actions.cancel
   			actions: {
   				title: '取消绘图',//'Cancel drawing',
   				text: '',//'Cancel'
   			},
   			finish: {
   				title: '完成绘图',//'Finish drawing',
   				text: 'Finish'
   			},
   			undo: {
   				title: '删除最后绘制的点',//'Delete last point drawn',
   				text: '',//'Delete last point'
   			},
   			buttons: {
   				polyline: '绘制一个多段线',//'Draw a polyline',
   				polygon: '绘制一个多边形',//'Draw a polygon',
   				rectangle: '绘制一个矩形',//'Draw a rectangle',
   				circle: '绘制一个圆',//'Draw a circle',
   				marker: '绘制一个标记',//'Draw a marker',
   				circlemarker: '绘制一个圆形标记',//'Draw a circlemarker'
   			}
   		},
   		handlers: {
   			circle: {
   				tooltip: {
   					start: '单击并拖动以绘制圆',//'Click and drag to draw circle.'
   				},
   				radius: 'Radius'
   			},
   			circlemarker: {
   				tooltip: {
   					start: '单击“地图”以放置圆标记',//'Click map to place circle marker.'
   				}
   			},
   			marker: {
   				tooltip: {
   					start: '单击“地图”以放置标记',//'Click map to place marker.'
   				}
   			},
   			polygon: {
   				tooltip: {
   					start: '单击开始绘制形状',//'Click to start drawing shape.',
   					cont: '单击继续绘制形状',//'Click to continue drawing shape.',
   					end: '单击第一个点关闭此形状',//'Click first point to close this shape.'
   				}
   			},
   			polyline: {
   				error: '<strong>错误:</strong>形状边缘不能交叉！',//'<strong>Error:</strong> shape edges cannot cross!',
   				tooltip: {
   					start: '单击开始绘制线',//'Click to start drawing line.',
   					cont: '单击以继续绘制线',//'Click to continue drawing line.',
   					end: '单击“最后一点”以结束线',//'Click last point to finish line.'
   				}
   			},
   			rectangle: {
   				tooltip: {
   					start: '单击并拖动以绘制矩形',//'Click and drag to draw rectangle.'
   				}
   			},
   			simpleshape: {
   				tooltip: {
   					end: '释放鼠标完成绘图',//'Release mouse to finish drawing.'
   				}
   			}
   		}
   	},
   	edit: {
   		toolbar: {
   			actions: {
   				save: {
   					title: '保存更改',//'Save changes',
   					text: '保存',//'Save'
   				},
   				cancel: {
   					title: '取消编辑，放弃所有更改',//'Cancel editing, discards all changes',
   					text: '取消',//'Cancel'
   				},
   				clearAll: {
   					title: '清除所有图层',//'Clear all layers',
   					text: '清除所有',//'Clear All'
   				}
   			},
   			buttons: {
   				edit: '编辑图层',//'Edit layers',
   				editDisabled: '无可编辑的图层',//'No layers to edit',
   				remove: '删除图层',//'Delete layers',
   				removeDisabled: '无可删除的图层',//'No layers to delete'
   			}
   		},
   		handlers: {
   			edit: {
   				tooltip: {
   					text: '拖动控制柄或标记以编辑要素',//'Drag handles or