rkflashtool: new version(?)

[ildar]

see at https://rkflashtool.svn.sourceforge.net/svnroot/rkflashtool
not sure how good is it.

[dpavlin]

Comparing diffs, it implements erase (which is basically putting 0xff all over the flash) and somewhat nicer one-line output of progress, but I don't see any code changes related to functionality.