docs: revisions to the sdk doc template for preview sdk, remove ndk download table for offline docs
docs: revisions to the sdk doc template for preview sdk,
remove ndk download table for offline docs

Change-Id: I13da1e5ab825f1d5c6a19ef9a76c36a3edd88bf6

xorware/android_build,xorware/android_build,RR-msm7x30/platform_manifest,xorware/android_build,xorware/android_build,xorware/android_build,hagar006/platform_manifest,pranav01/platform_manifest,fallouttester/platform_manifest,see4ri/lolili,knone1/platform_manifest,ND-3500/platform_manifest,Hybrid-Power/startsync