[ADD] request for url
[UPDATE] HelloEgret Template
[ready] v1.5.1
[Ready] to release

[ADD] load from sd card
[UPDATE] HelloEgret.java template file
[ADD] some comment for usage
[FIX] c++ syntax warning
[UPDATE] version number to v1.5.1
[UPDATE] HelloEgret template file
[UPDATE] HelloEgret.java template
Merge branch 'release/1.5.1'