#211 ECO source file has errors

[Drew Ferguson]

A few errors occur in the ECO source file src/data/eco.orig
These errors prevent src/make_eco_bin.sh from generating an eco.bin file

• line 12280: 7...d6 should be 7...a6
• line 15636: 5...bxc3+ should be Bxc3+
• duplicate entries: 5860 (B51.0008) - 5907 (B53.0007) - these two lines lead to the same position - evidently the respective program doesn't expect this (patch comments out line 5907)

A patch is attached to correct these errors.

The should be downloaded to src/data and applied with

patch -u eco.orig -i eco.orig.patch