Update docs to reflect current codebase.
Update docs to reflect current codebase.

- Reformat to use one sentence per line.
- Update the text to reflect today's codebase
- No documentation of client/server and multi network options yet.
That will be added once the code settles a bit.

dcbw/flannel,bprashanth/flannel,bprashanth/flannel,ingvagabund/flannel,eyakubovich/flannel,coreos/flannel,endocode/flannel,lvlv/flannel,dcbw/flannel,imzhulei/flannel,MohdAhmad/flannel,eyakubovich/flannel,kelcecil/flannel,imzhulei/flannel,endocode/flannel,cusspvz/flannel,svdata/flannel,wikimedia/operations-debs-flannel,coreos/flannel,MohdAhmad/flannel,imzhulei/flannel,MohdAhmad/flannel,ingvagabund/flannel,cusspvz/flannel,wikimedia/operations-debs-flannel,lvlv/flannel,ingvagabund/flannel,kelcecil/flannel,sujitfulse/flannel,kelcecil/flannel,dcbw/flannel,lihuanghai/flannel,Yhgenomics/flannel,wikimedia/operations-debs-flannel,endocode/flannel,sujitfulse/flannel,jonboulle/flannel,adiclepcea/flannel,jonboulle/flannel,bprashanth/flannel,cusspvz/flannel,lvlv/flannel,adiclepcea/flannel,EverythingMe/flannel,EverythingMe/flannel,EverythingMe/flannel,jonboulle/flannel,coreos/flannel,svdata/flannel,sujitfulse/flannel,adiclepcea/flannel,eyakubovich/flannel,Yhgenomics/flannel,lihuanghai/flannel,svdata/flannel,lihuanghai/flannel,Yhgenomics/flannel